Stuck Engine - help needed

[angelfj1]

To my BCF friends: I posted this today on the Triumph forum. I decided to repeat the post here in the Restoration & Car Care Area because it deals with a basic engine problem. And, a 4 cylinder, wet-liner, TR-3A tractor engine is about as basic as you can get. Hope you can help.

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First of all, please excuse the long post. I know there is an answer out there, so I tried to be as descriptive as possible.

We have encountered a strange situation with the engine in my project 3A. We began the restoration of this car, TS58476LO in November 2001. During the summer of 2002, the original engine, TS58681E was completely rebuilt. Just in case questions arise as you read about my dilemma , as finished at that point in 2002, the engine included everything but intake and exhaust manifolds, distributor, valve gear, and fuel pump. The block and cylinder head, sump and timing chain were painted with epoxy high-gloss paint. The flywheel and clutch were attached. All openings were sealed and the entire engine was bagged in plastic with lots of desiccant. It has been in dry storage for almost six years with the original assembly lubricant and sump completely filled with 30W oil since then. To my knowledge, up until last week the engine was never "turned over" manually or by starter since the rebuild.

Fast forward to last week, the current state of the restoration is a completely restored body shell mounted on the completed rolling chassis, including front and rear suspension, engine, clutch, O/D transmission, prop shaft, differential, brakes, fuel and brake lines, wheels, tires, etc. The "engine" now includes intake and exhaust manifolds but no distributor, fuel pump, carburetors or valve gear. Last week the refurbished starter was installed and the engine was cranked very briefly – mainly to test the starter, and the engine did rotate several times. We stopped only because the battery was flat so we put it on charge overnight.

The following morning I added the valve gear and was preparing to adjust the valves. The plan was to rotate the engine through the transmission by using a large socket and breaker bar and to rotate the nut on the transmission output flange, with the transmission engaged in 4th gear. Before proceeding, I lubricated the engine by using a long extension and a cordless drill to spin the oil pump through the hole in the distributor pedestal. After a few seconds we had good oil pressure and the top of the cylinder head was flooded. We knew that the oil gallery was full and that the mains oil ways and bearings had lubrication. Attaching the socket and breaker bar to the transmission output flange nut we tried to rotate the engine. We were only able to turn the engine (verified by watching the crankshaft pulley) about 30 degrees before encountering a large resistance. When we tried to increase the force applied, all we accomplished was to slip the O/D brake.

At first we thought there was a problem with the starter/ring gear. Removal of the starter revealed nothing obvious. No obstructions could be seen. With the starter removed we tried again to rotate the engine with no luck – got the same resistance at exactly the same point in rotation.

We then suspected a problem in the transmission. We rigged up a manual lever since the clutch slave/master cylinders are not yet connected and we wanted to avoid removing the transmission if possible. With this lever attached to the clutch cross-shaft arm we were able to operate the clutch and effectively disconnect the transmission from the engine. With the clutch disengaged we were able to select all 4 forward gears and reverse and rotate the output flange. There was no obvious binding or unusual noise from the transmission or O/D. We believe that this exercise has eliminated the transmission as the cause of resistance.

We returned our focus to the engine. We had a theory that after the successful rotation (with starter) last week that most of the assembly oil had been scraped off of the cylinder walls, thus possibly causing the unusual resistance. We also felt that we needed a better method of applying more torque to the crankshaft than what could be transferred through the transmission/OD. One concern we had was where best to apply torque to the crankshaft. We were concerned about using the fan hub extension for fear of shearing the woodruff keys. We decided to use an old 4-jaw lathe chuck and grasp the front of the crankshaft bolt. We applied penetrating oil to each cylinder through the spark plug hole and left the engine overnight.

In the morning (yesterday) we applied torque to the front of the engine (crankshaft bolt / 4-jaw chuck) – no luck – at least we did not feel comfortable applying more force through a longer lever-arm. What to do next? We decided to drop the oil pan and possibly remove the timing chain cover. This was to be done today and I am waiting for a call from the shop with a report of what they found.

This has me very frustrated. How/why did the engine turn over last week with the starter and now we seem to be stuck?

Let's face it. This is a 4 cylinder, wet liner tractor engine. How more basic can you get?

If you have encountered such a problem and/or have any suggestions I really would appreciate hearing from you!

Sincerely,

Frank
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FJA
Downingtown, PA
TR3A TS58476LO (under restoration)
TR250 CD1510LO

 

[eschneider]

If I understand correctly, you said it turned before you installed the valvetrain, and wouldn't turn afterward? What happens if you remove the valvetrain again?

Question - you said it rotates about 30 degrees before it hits resistance. Does it rotate back from that resistance with relative ease? In other words, are you hitting a "Stop", or is it "stuck"?

Is the resistance encountered with 2 pistons at TDC, or at some random height in the cylinders?

 

[angelfj1]

eschneider: Allow me to clarify?

As soon as the resistance was noticed we removed the rocker gear and that bit has been off since.
We did try the starter with and without the rocker gear and stalled the motor with a fresh battery and charger/booster unit.
Neither the distributor nor fuel pump are attached at this time - in other words, nothing is being driven off of the camshaft.
The resistance that we notice is not abrupt. It is more like a build up followed by a solid stop. We can rotate clockwise perhaps one-eigth turn then build-up in resistance. At that point we can reverse direction and rotate anti-clockwise the same distance.


I hope this sheds light on the problem I really appreciate your insight. Thanks

 

[PAUL161]

I'd like to throw in my 2 cents worth. If the engine was setting for quite a time and after you opened it up and then turned it over with the starter, did you soak the the tops of the cylinders with lube before doing this? I hate to say it and I hope it's not the case, but since your talking about a rebuilt engine that has never been run, you could possibly have galled one of the cylinders if it was dry for a short time and the pistons and rings were a tight fit. Dry rings, dry cylinder, not a good scenario. If it was me, I'd pull the head <span style="text-decoration: underline">if nothing else is </span><span style="text-decoration: underline">apparent</span> and look at the cylinder walls. If one is scored, I'd tear it down, hone the cylinder and install new rings. Hopefully it's something more simple. But this is a possibility.

 

[angelfj1]

Paul: These are all great comments which I will ask the mechanic who is working on this project. I was told that all of the surfaces were coated with assembly lubricant during the rebuild, including the cylinder walls. The sump has had oil since the rebuild also. Last week we pressurized the oil system by turning the oil pump through the hole where the distributor goes. We got a very forceful flow of oil in a few seconds, including the top of the cylinder head through the feed hole where the last pedestal goes.

next in the plan is to drop the pan.

thanks for the comments.

fja