TD engine rebuilt - play by play

John is recovered from foot surgery and has a busy social schedule for the next several weekends, so yesterday was the day. I spent the day before cleaning all the parts and nuts and bolts in kerosine while recheking my inventory. I looked more closely at the sprockets for the timing chain as well as the pushrods and decided to make a panic trip out to Skip Kelsey's

Weather has been pretty miserable in Northern California and the trip ate up most of the afternoon, but was able to get Skip's opinion on some parts

Ended up replacing the (smaller) crankshaft sprocket and the oil thrower as well as three of the pushrods, which had loose ends. The chain tensioner is in excellent condition so was salvaged. The handle had broken off the water drain spout so it was replaced as well. I had already purchased the gasket set, pistons and other parts, as detailed in earlier postings to this thread

John arrived promptly at 8:30 Saturday morning and we set to work. It soon became obvious that you can't have too much bench space, so I set up a 4 foot square plywood platform on sawhorses in addition to my workbench and a shop mate. The engine was already on the stand

The machine shop had installed the new cam and the oilpump, getting the pump clearances right with the unit on the engine

We started by checking the main bearing clearances, which John prefers to do with a micrometer, rather than with plastigauge. All was in order so we proceeded to the thrust bearing (on the central main bearing) clearances

Things were a little tight so we shaved them on 360 grit wet and dry emery paper, lubricating with kerosine

Since we hope to have the engine running within a few weeks we lubricated each part with simple motor oil

After that we worked on the rear oil seal. John doesn't like the Moss upgrade for this seal, nor does he do all the fussing detailed in Horst Schach's book. He maintains that the seal is well designed and suffers mostly from people overtorquing the mounting nuts. This distorts the shape of the seal and allows oil to leak around the edges. His car doesn't drip oil, so we shall see

Next came the pistons, starting with checking the gaps in the rings . .

all correct. What really makes this project work is the deserved respect John has for Darryl at the machine shop. He had already installed the wrist pin bolts so we didn't have to worry about special wrenches. The rods had all been balanced and are clearly numbered. Bearing clearances were all correct by micrometer

The first piston installed smoothly from the bottom using the compressor

The second kept hanging up as the first ring entered the cylinder. The size of the ring compressor made alignment difficult. Rather than force the piston, we inserted it without the rings from the bottom and brought it out through the top to install the rings. Gentle but firm tapping (certainly more than with the heel of the hand) with a rubber mallet did the trick. We did number 3 and 4 pistons that way

The crank then went in for the last time, torquing all of the nuts. We switched the nuts around to make the holes line up for the safety wire, and only had to file down one nut to make everything match at the proper torque

Rod bearings were next, using new nylon bushed nuts which don't require safety wire. I was concerned over the stiffness as we turned the crank, caused by the rings dragging in the cylinders. John assures me that this is desirable at this point and will keep our compression and oil pressure where we want them

Next came the worry over correct setting of the timing chain. The chain supplied had two lighter colored links, but counting the correct number showed that they were not appropriate for our purposes. A couple of dabs of white paint on other links gave us the correct 13 on one side and 15 on the other as specified. We then had to work a little with the new keys on the crank and new camshaft. The pros in the readership may already see what's coming here. We counted and aligned and installed both sprockets and chain before realizing that we hadn't installed the front mounting plate. Both sprockets had been driven on, and my lightweght gear puller wasn't up to the job. Anyway, it was time for lunch

Over hotdogs and beer (small glasses) we decided to borrow a gear puller from my local mechanic. I hate to ask a pro to loan his tools, but he had our family car in for battery work that morning and we were anxious to complete the job. He graciously loaned us a sophisticated two armed puller with a central split rod that keeps the two arms together. Clearance was tight against the block and I worried about the puller on the side of the chain, but patience and perseverence paid off. Front plate was installed, sprockets were replaced and links were once again count.

The new head studs have arrived, and we also got hardened steel washers, so all is ready

John will call when he returns and we will probably put it together on Tuesday evening. I'm assuming we'll leave the manifolds, starter and generator off the engine until after paint

I spent yesterday cleaning and degreasing the transmission case to be ready for paint. I also cleaned the grease out of the enigine bay and front of the chassis

I'm looking through the parts catalogues and will probably replace the clutch throw-out bearing before putting the thing back together. Are there any other landmines that I want to avoid? (as in simple parts that are prone to failure that should be replaced while the engine is out)? Stay tuned, we're getting closer

Next chapter. John got the timing chain cover holes treated with helicoils and I got the new head studs

We started out Tuesday evening, asssembling the chain cover and the sump with no problems. We sorted out the bolts and lockwashers and had enough to go around. Used a small amount of silcone gasket sealer between the block and the paper gaskets, none between the covers and the gaskets. Oriented the cork rear seal correctly according to the long or short offset and used a lot of sealer on it and the front seal around the crankshaft. (A lot is a relative term . . . we made sure there would not be enough to ooze into the sump and eventually clog the oil pan.) Now with the front and bottom of the engine closed it was time for some self congradulations and a break for dinner. We decided to have a look at the head studs just before recess. We found that the studs as supplied were a tight fit into the block. They turned with considerable force on two nuts backed together, using only an end wrench. I decided to lubricate the threads, so pumped a little oil into the hole. As John was tightening the right front stud we heard a sharp crack and saw oil oozing out of a crack in the front of the block, extending just over an inch vertically from the top, just outboard of the water pump recess

Later testing with the other (long thread) end of the new studs and with the old studs found that they could be screwed in with finger force only. Our conclusion is that the studs are just a little oversize on the short thread side (a warning to other engine rebuilders!) and that adding the oil to the hole produced hydraulic pressure enough to crack the block

Dinner was a little glum, with speculation on what could be done. We conjured up images of having to disassemble the whole thing so that the block could be welded. All of these months-long projects do come down to a timetable, which was rapidly falling apart

A call to Darryl at the machine shop allayed some of our fears. He could retap and helicoil, making it strong as ever. He would have to construct a jig to make sure that the hole is perfectly vertical, but all I need to do is get the engine down to him

Next problem is moving the heavy unit. I took it to and from the shop in the back of my Mini van. In various parts I was able to lift it with only a little lower back pain, but now the crank and flywheel are in the block and the engine is on the stand. I rented a hoist to get the whole thing out of the car, but don't want to make the trip across town, asssemble and reassemble the hoist, and all that

Time to think (I do my best planning in shower, which uses up a lot of hot water.) The Mini deck is about 10 inches off the ground and the sump is up about 16 inches with the engine on the stand. I rolled the stand up to the back of the Mini, with the legs between the back wheels and the engine suspended inside the Van. I then jacked up the rear of the Mini until the weight of the engine was just taken off the stand and backed off the bolts holding the back of the block to the stand, then lowered the jacks

I deliverd the engine to Darryl a couple of hours ago and he will call me when it is ready. He says that helicoils go a great job of spreading the load, and they will sometimes tap a brand new block and insert helicoils to prolong the life of the block. John plans to chase the threads of the studs which should make them fit easier into the block

So, progress limps along. John and I still have to install the head, then the rocker assembly and set the valves. Then the water pump and outlet and the generator mounting plate. Then I'll mask off the manifold ports and the flywheel opening and spray the whole thing

The sump (and all the engine, for that matter) is a grey aluminum color. Any votes for leaving it that color while painting the engine and transmission the correct maroon? I already have the "incorrect" chrome valve and side covers

John brought his set of taps and dies and we chased all the threads in the block. He had an adjustable die for the threads on the studs and we shaved a little off of each (about a half turn on the set screw) before they would screw into the block with finger pressure only

We used a 1500 TF head gasket (the cylinders are bored to .100 over). The gasket has round holes for the water passages, while the block has the bannana shaped ports. The head itself has round ports and Skip assures me that his engine has the same apparent mismatch with no problems. John's explanation is that these engines undergo many modifications and parts swaps in their lifetime, so almost any combination is possible. He said that if we have a problem with overheating we can always change for a different gasket (though I don't know that I can accomodate my cylinder size in a gasket that has bannana shaped water ports.) We used some brake grease on both sides of the gasket and then torqued it down according to the sequence in the manual. 10 lbs at a time up to 50

We then installed the rocker arm assembly (new shaft and bushings had been assembled at the machine shop) and set the valves to .13. After about 500 miles I'll retorque the head nuts and set the valves at .012 with the engine warm

Everything else went together smoohtly, with only a little searching for the correct nuts and bolts. I have the later style horizontal oil filter cannister so there were three mounting holes under the dipstick that needed to be plugged . . . they communicated right through into the sump. Found some 8mm by 1mm bolts at the local Grand Auto that did the trick

I now have the spin-on filter adapter, so needed to get that screwed in tightly over a new washer

Weather was fairly decent over the weekend (a respite from El Nino rains) and I spray painted the engine and transmission. I bought the PPG enamel color specified in Schach's book. Primer first, lots of masking and then paint

It all looks pretty spiffy ( a darker maroon color than I had anticipated) but now I have missed another soft deadline

We are on our way out of the country for a two week trip that will consume the next three weekends, so the engine will have to sit on the stand until the end of March

I have a target date of March 28 to get the team and the engine hoist together for the job. I'll need to squeak out some time before that to finish installing the bearings in the pedal box and bleed the brake system

How come these projects that take months to complete always come up with deadlines like this?

Bitten by stripped threads - again!

After a recess of three weeks caused by the intrusion of my professional life (I hate it when that happens) we finally planned engine replacement day last Saturday

I spent a fairly unpleasant half day grunting in and about the pedal box, replacing all the bushings. I had a friend weld the hole for the clutch clevis pin, restoring the round shape. Advice to those who are in the early stages of a frame-off . . . do all the pedal box work before the tub or the engine are back on the chassis. The parts are cheap and very difficult to reach in the intact car

There were a few other last minute touch up points on the engine compartment and I replaced the seals around the carburator jets, since they had been running rich. I also attacked the inlet manifold with my Dremel tool, tapering the inlets to match the newly machined ports (and gasket). No radical removal of metal, just tapering the rim to avoid any turbulence. I flushed the radiator and checked parts inventory, ready for the big day

I rented the engine hoist early Saturday and John arrived ready to go. He had taken my distributor home to clean it up and check the shaft and weights. We installed it and set the timing to about 5 degrees after TDC. We installed it with the low tension lead to the rear (we'll have to change the plug wires around) to avoid the earlier problem of the rev counter reduction gear shorting against the terminal. When he rechececked the timing it was off a few degrees so we checked and found that there was excess motion between the driving gear and the distributor shaft. Closer inspection found that the gear had been mounted with a piece of finshing nail instead of the pin, and the fit was poor. We were able to fashion a better pin out of a larger concrete nail, ground down to a tight fit on the grinding wheel

Manifolds mounted well after we found the nuts. I'm still amazed how often I can't find the proper nuts, even though EVERY nut and bolt went directly into a labeled celophane bag during disassembly

John brought a piece of shaft that served as a clutch alignment tool while we assembled the clutch to the flywheel. We found the marks that the machine shop had placed during balancing, to orient the plate properly, placed the alignment shaft through the clutch plate into the spigot bearing and torqued down the mounting bolts

Finally everything is mounted and ready to go. We picked the engine up with the hoist and gently lowered it to the ground. We then slid the transmission up and, after placing it in gear to help engage the shaft, started bolting on the bell housing. Two of the holes along bottom half of the sump rim were stripped and another partly so. Horst Dach had included among necessary tools a set of 8 by 1mm helicoils, but I hadn't been able to locate that size at the local Auto supplies store. Big mistake

So we left the engine on the garage floor and returned the rented hoist

John will contact the machine shop and borrow the helicoil set and we'll try again next week

I wish I had asked the machine shop to check and restore every thread in the block and pan, but that's hindsight now. I don't know if such checking should be standard practice, but I sure recommend specifying it in your future rebuilds

The tarnished silver lining in this is that I now have a little time to get some of the proper washers nuts and bolts that we were working around, and of course, the engine will sound all the sweeter when we finally get this thing done

RE:the rear engine seal. I don't recall that there was any torque specification. John took the seal housing home and straightened it out (it was warped from prior tightening). Installing it we took care to tighten until snug, with no tendency to distort the housing. Obviously, I haven't been able to see if it works yet

I got the engine hoist from the rental place, again . . . we're on a first name basis by now . . . and John arrived with the helicoils. I had gotten the needed parts from Skip; the proper bolt for the distributor bracket and a key for the water pump pulley.

Had trouble getting the key to stay on the shaft as the pulley was pushed on . . . the key kept getting embedded in the felt washer around the shaft.

Finally invented a part from a large washer with a groove filed to accept the key. Pushing the washer over the back part of the key kept it from sliding out the back of the keyway as the pulley pressed down on the front of the key. The washer was then driven backwards by the pulley.

Anyhow, we helicoiled all of the holes around the sump flange which accept bolts through the bell housing. We hoisted the engine and let it rest part of its weight on a Shop-mate work table. We then put the transmission on a second Work-mate and shimmed it with 2 by 4 blocks to make the holes match up, then bolted them together. We put the rear motor mount rubber (new) into the housing and compressed it with the weight of the transmission against the workmate by lowering the hoist a little more.

Jack (a new TC owner) stopped by at an opportune time and the third set of hands was helpful it getting the assembly into the engine bay.

I had removed the flange on the steering pinion to reorient the steering wheel and it was helpful to have it out of the way as the engine slid into place. It was still tight, clearing the steering pinion on the left and the bracket for the engine steady on the right. With the weight of the engine out of the car, the front wheels towed in enough that the engine hoist wouldn't pass between them. We used two jacks near the crossmember under the cowl to lift the wheels off the ground. After the hoist was pushed back, lowering the engine to clear the firewall, we released the jacks. Then we used one of the jacks under the transmission to get the drive shaft flange to go over the crossmember. A little more backward motion and the motor mount holes matched.

There was still a lot of work to do to attach all the parts, and we resolved to get the vital parts in to fire up the engine. We installed the radiator but left those nuts over the steering rack for a later day. Carbs installed after some modification of the choke mechanism, which had been reversed by some previous owner. John had rebuilt the starter and generator and these installed fairly easily. We attached the steering before installing the generator.

Finally all was ready, so we added water and oil. The last time I had the sump off I had borrowed a pressure oiler from Skip, but my schedule didn't allow the trip out there, so we were without.

We left the sparkplugs out and the ignition off while we cranked the engine on the starter. We used a pump oil can to fill the reservoir on the pump, through the plug supplied for that purpose, but after almost five minutes of cranking (with rests to preserve the starter) there was still no oil pressure. We disconnected the line to the gauge and pumped oil down it, then removed the oil filter (I had installed a new spin-on adapter) and pumped oil into the center hole in the filter housing.

I was about ready to despair when the pressure jumped to 40 pounds. We installed the plugs and turned on the ignition and it fired on about the third revolution.

It's quiet and smooth, though I still can't get the front carb lean enough.

I took the carbs apart again and replaced the gland washers with new cork washers soaked in 3-in1 oil, but apparently that's not enough. Next step is to replace jets and needles.

The valves are whisper quiet and John says I should reset them to .12 when the engine is warm. He likes to hear them a little to know they aren't too tight.

By now it was sundown, so driving has to wait for another session. The sound is sweet, but I still have to get those carbs adjusted.

A major challenge in reassembly is fitting the gear shift mechanism back on the transmission. How do I get the dog on the end of the shift lever into the space between the shafts and get the whole thing bolted together? Suggestions welcome.

Also, what spark plugs should I be using? The Champion L10 S specked in the manual no longer exist and my local Grand Auto wasn't able to figure out the cross reference to anything he had in stock.

The road beckons, but not for another week.

I then crawled under the front and bolted the bottom radiator stays. I had forgotten how much fun that is when the steering rack is in the car

I changed the transmission oil and attached the clutch. I have spoken too harshly about my romps through the pedal box, so I was punished by discovering that I had installed the clutch lever upside down (not obvious until I tried to mount the link on the sump). I'm getting to know that little place pretty well

I put the shift mechanism back on with a little difficulty, and tested shifting to first and second. (note that for later)

Then the cowl and floorboards, with some of the screw holes on the side of the cowl not lining up. With help from my daughter (she's home from college for Easter and I promised her a seat for the first test drive) got the nuts back on for the seatbelt anchors. Then the carpet seats and all that

Started her up and backed out of the driveway without trouble. Drove around the block but couldn't get into third or fourth gear. It was late, so retired for the night

I thought the problem was lining up the dog from the shift lever into the shafts on the transmission. After inserting and reinserting several times (now considerably harder with the cowl installed . . . thought of removing the cowl, but that would mean removing floorboards, which means seatbelt anchors, etc., etc.) Finally took off the external housing or cap on the back of the shift mechanism below the shift lever, that covers the shifter for third and fourth (as found on later model shifters, see my disassembly posting of months ago) and after more trial and error found that the problem was not that the dog was misaligned, but that the shaft is bent enough that it is siezed by the housing. I had worried whether I had bent that shaft in removal, since I didn't understand the external housing, at that time. I got it to shift okay if I leave the bolts that hold the cap in place backed off about half a turn. Carpet and seats went back in and the hood went back o n (no paint mishaps!) and we were off! Though I brought a set of tools and warned my daughter that a shake-down trip would probably require some mechanical adjustments, I only had to stop once to increase the idle speed . . . it stalled at stop signs. Got some gas (its first tank of un treated unleaded) and had some anxiety over a delay in warm starting. It started up with the accelerator depressed about half way

Oil pressure is steady at 60 to 70, and water temp is about 62 (ambient temperature was low 50s) Except for occasional sputter at mild acceleration, it is smooth and quiet, well quiet for an MG. I hope the sputter will disappear when I get the carbs adjusted properly. I'm running in slowly, so we kept on back roads and low revs

Overall assessment . . . I'm a little disappointed at the power, at least after the first 30 miles. It's definitely a smoother engine than the one I took out several months (and dollars) ago, but it's not a completely changed car. I did keep it to low revs, so don't know what it might be capable of, but gear selection up hills (we live in the hills) was often third and second. I continue to have misgivings about my final plan to increase the rear end ratio from the stock 5.25. I don't have the repaired rev counter yet, so don't know how fast the engine is going. The rebuilt speedometer registers 50 when I'm keeping up with traffic in a 35 mile zone, so I don't have any objective parameters. I hope that the carb adjustment will add some zip. I think I misreported our timing setting in an earlier posting . .

It's set at a few degrees before TDC

Plans for the weekend include carb adjustment after it has warmed up on a brief run. I'll also reset the valves while warm and re-torque the head. The tach should be ready this week. I will have to modify a large washer or similar to offset the transmission shaft housing

So, here's the summary with unsolicited advice for those about to embark on an engine rebuild

I won't review the whole play by play novel but the details are there

Total time; five months. That includes interludes for Christmas, John's surgery and a three week trip away from home, plus the usual amount of family responsibilities

We could have shaved a month off that time with helicoil precautions, and the advice remains to have the engine shop helicoil all the aluminum fittings (the sump and timing chain cover) Total cost; about $4500. That is based on a machine shop cost

Spent a chilly Saturday on the first long drive (about 170 miles) with no major problems. The car is running smooth and quiet, and seems at peace with the TF 4.875 ratio. I've been staying below 3000 rpm (occasional jumps to 3500) for the run in period

A few quirks: The motor has brief periods of missing or hesitating, with no pattern that I can figure out. It's usually between 2000 and 3000 rpm, sometimes during acceleration but other times at stable speeds. It's as if someone switched the ignition off and then back on (though there is no backfire). By reflex I give it more gas and after a couple of sputters it evens out. I rechecked my carb adjustment and it seems about right, both by Color-Tune and lift the piston. The spark plug electrodes are a nice tan color and there is no exhaust smoke. I re-set the valves, though they were still pretty close. I also retorqued the head while the engine was warm, though I'm sure that didnt' have anything to do with it

I wonder if the fuel pump is having trouble keeping up, but it didn't happen at all during a brief freeway run at 32 to 3500. With all the talk of heat shields I wonder if this might be the problem. I plan to recheck the timing next weekend. Suggestions? Another annoyance is that my temperature gauge stopped working. It's a new dual gauge which has about 1200 miles on it, but it faded to 0 (30, actually) during a short drive to the barber shop. I later thought I smelled ether in the cockpit. I was fiddling with dashboard wiring, but don't see any kinks or breaks in the sensor line

Now that the motor is so quiet I hear a little noise from the left front wheel. When there is lateral load, as in even mild cornering to the right, there is a hissing or friction sound that sounds like sandpaper held against a spinning disk. It doesn't seem to affect performance but I hear it even with steering corrections to the right. I checked the hub nut, which is tight, and readjusted the brakes. There is about a quarter inch of play in the steering arm on that side. Should I worry about this or investigate further? In answer to a prior question, there is virtually no oil leak (this is an English car) from the engine, using the standard rear oil seal, which we straightend and installed correctly . . . without too much torque that would bend the plate

My top and tonneau cover shrunk while off the car. They are both aftermarket canvas, I think (look like sailboat sails to me) in good shape, but I can't stretch them to fit. Has anyone addressed this problem successfully? I'll try a local upholstery shop for ideas

Now I'm waiting for California weather to act like spring (it's raining again today) so I can try to wear the roads out

Safety fast!