Stuck Engine - Need Help!!!

[angelfj]

Hi Frank,

with the big ends undone you should be able to push the pistons up the bore although they may be stiff. No need to remove head to test piston movement.

 

Just to cheer you up I have had a lateral thought - movement is 'the rate of change of distance'. Rate = time.

Quite clearly you have encountered an area of galactic temporal absence where time stands still (usually found on the Isle of Wight). I remember this from an episode of Startrek.

 

Keep smiling, you will find the answer

 

Roger

Roger et al:

Saturday, October 04, 2008

 

Update on stuck engine.

 

This morning we accomplished the following:

 

 

Removed all con-rod bearing caps. Upon examination the crankshaft journals and bearing shells appear perfect and are still liberally coated with assembly lubricant.

 

With the con-rods free from the pistons, we could easily (with one finger) move the pistons up and down in their cylinders.

 

Tried to rotate crankshaft – frozen – can't rotate in either direction

 

Removed the center main bearing cap, shell and thrust bearings. Again, the crank journal looked perfect. Examined shell and thrust bearings – they look perfect.

 

Tried to rotate crankshaft – frozen – can't rotate in either direction.

 

Did not remove the rear or front main at this time. May have to later if our new theory is flawed.

 

While under the car we used a length of SS wire to push up on the bottom of each lifter. All eight lifters moved smoothly in their bores. All eight push rods were removed (one at a time) and checked for length and straightness. The measurements are exactly the same as recorded six years ago.

 

Removed the transmission and clutch. Found nothing wedged between the ring gear and bell housing. Transmission input shaft, clutch and flywheel look perfect.

 

Note: the crankshaft and camshaft are now completely frozen. There is absolutely no motion possible, not even what you would expect with normal slack in the timing chain. Whatever is causing this problem has gotten worse since last week we were able to rotate the crankshaft about 30 degrees forward and reverse.

 

So far we have eliminated stuck pistons, valve gear, transmission, clutch, ring gear and bearings.

 

We have a new theory. Whatever is causing this problem prevents motion of both the camshaft and crankshaft. Normally there is a small amount of relative motion possible between the two due to the slack, albeit small, in the timing chain. However, now both are frozen solid. We suspect a problem where something, possibly a piece of the timing chain has broken and lodged between the two sprockets.

 

Tomorrow or Monday we'll remove the timing chain cover and see what's going on inside. I hope to post another at that time.

Edited October 4, 2008 by angelfj

[Alec Pringle]

Hi Frank,

 

or possibly a broken tensioner which has locked chain and sprocket ?

 

Cheers, and sympathies,

 

Alec

[w_eden]

Apologies if you've already eliminated this but:

 

You say you turned the engine over on the starter brieflt, then primed the oil ways with a drill and extension. Did you then fit the oil pump drive that engages with the cam? Could this be the issue?

 

Hope it ends up being something simple!!

[angelfj]

Hi Frank,

 

or possibly a broken tensioner which has locked chain and sprocket ?

 

Cheers, and sympathies,

 

Alec

 

Yes, indeed!

 

Trust you are well matey!

 

Frank

[angelfj]

Apologies if you've already eliminated this but:

 

You say you turned the engine over on the starter brieflt, then primed the oil ways with a drill and extension. Did you then fit the oil pump drive that engages with the cam? Could this be the issue?

 

Hope it ends up being something simple!!

 

W. No, the distributor drive is not in.

 

Thanks you for the suggestion.

 

Frank

[Rhodri]

Frank, get out there and let us know, very soon, what the cause is..the suspense is killing me !!!

 

Rod

[angelfj]

Frank, get out there and let us know, very soon, what the cause is..the suspense is killing me !!!

 

Rod

 

 

Rod: Understood! Think how I feel.

[Chris59]

Just my experience :

 

A valve can sized herself in his guide, especially when new, even when engine is running.

I saw this 2 times, only on wet TR liners :

1) with valve gears on, nothing move if you turn it one way, but can move slitghly on the opposite way,

2) a sized valve, if sized open, can oppose an incredible force to a piston, but should not bend, if the piston is flat (the valves are "verticals").

 

 

A camshaft can get stuck in an engine, but unlikely when it's not running :

I saw this in a MK3 Spitfire : the crankshaft welded himself in the engine block on his journals, destroying the engine bloc when he broke in 2 parts in the middle.

 

Hope you understand my poor english , sorry !

 

Cheers,

Chris.

[angelfj]

Just my experience :

 

A valve can sized herself in his guide, especially when new, even when engine is running.

I saw this 2 times, only on wet TR liners :

1) with valve gears on, nothing move if you turn it one way, but can move slitghly on the opposite way,

2) a sized valve, if sized open, can oppose an incredible force to a piston, but should not bend, if the piston is flat (the valves are "verticals").

 

 

A camshaft can get stuck in an engine, but unlikely when it's not running :

I saw this in a MK3 Spitfire : the crankshaft welded himself in the engine block on his journals, destroying the engine bloc when he broke in 2 parts in the middle.

 

Hope you understand my poor english , sorry !

 

Cheers,

Chris.

 

Chris: Your english is fine!

 

This engine has NEVER been run. We have verified that the cam followers and pushrods as well as the valves are clear to move. Thanks for your suggestions.

Edited October 5, 2008 by angelfj

[angelfj]

 

Eurika!!!

 

This has been a real PITA and has caused a lot of lost time BUT we avoided having to remove the timing chain cover.

 

These flywheel bolts were special order grade 8 . They have an area just below the head which is un-threaded which helps to index the flywheel with the rear crankshaft flange. Our theory is that during engine assembly this was not detected because the interference was small enough and motion slow enough that no material (aluminium) had yet been plowed from the bearing housing. Literally years later, when the starter spun the engine at high speed the material began to build up. This continued until we eventually reached a point that we could not overcome even with approx. 1000 lb-ft of torque applied.

 

Another interesting point, you may have noticed that this is an alum. flywheel which is approx. .070 thicker at the bolt hole than a conventional cast iron unit. So, had we used a stock flywheel we would have discovered this problem during engine assembly.

 

Live and Learn.

 

 

[Chris59]

Congrats !

[angelfj]

Pictures are better than words.

 

[pfenlon]

Frank I have been watching this saga from the beginning, if there had been a heist, and a good murder as well, you would have had a best seller on your hands.

 

I of course thought it would be something like that, just jesting, glad it was a cheap fix if not time consuming.

 

when I test ran my TR4 engine after a 4 year rebuild (without the body on) I proudly sat and looked for a nice dry engine as it ticked over, then the drip started from the rear main, hadnt drifted enough wadding in, out it came etc etc so I have much sympathy.

 

Make sure you shoot the bolt supplier!

Edited October 8, 2008 by pfenlon

[Rhodri]

Blimey Frank- give us an easier one next time !!

 

Rod

[angelfj]

Blimey Frank- give us an easier one next time !!

 

Rod

 

Now, Isn't that the truth!

 

And,, thanks to all who contributed and offered support.

[Eyetee]

I was going to suggest that it might be the bolts on the flywheel

 

glad the trouble was no real trouble just a pita trouble

 

goes to show if the engine siezes dont automaticaaly reach for the scaffold tube, just systematically dismantle

 

enjoyed that, good post

[angelfj]

. . . . . . . dont automaticaaly reach for the scaffold tube, just systematically dismantle . . . . . .

 

I'm pleased that you enjoyed this BUT , american english translation, please

Edited October 10, 2008 by angelfj

[Don Elliott]

Frank - I'm only guessing as I also had never heard this expression before. A scaffold is where executions take place by hanging and if a TR owner is so upset with all that can go wrong, he may take it upon himself to do something rash - like climb the steps of the scaffold by himself and . . . .

[Alec Pringle]

Hi Frank,

 

Scaffold pole would be another term, it's what you use on the end of a wrench to achieve greater leverage . . .

 

see

 

http://en.wikipedia.org/wiki/Scaffolding

 

Cheers,

 

Alec

[Don Elliott]

Thank you Alec.

[BrianC]

I think I prefer Don's (mis)interpretation. If I'd had Frank's problem, I would probably have hanged myself by now. Glad it all turned out OK in the end.

[Chris59]

American to English to French : scaffold = échaffaudage

 

Not sure to understand

[Rhodri]

Chris- comme ca!

[angelfj]

Chris- comme ca!

 

Oh! Now I understand. But you need to realize that before the flywheel was removed we took a piece of steel bar stock and drilled 2 hole to correspond with 2 tapped holes opposite each other on the outer circumference of the flywheel (clutch attachment points). Once this was bolted in place our intrepid mechanic fitted a 4 foot length of steel pipe to this "lever" and was able to hang on it. This guy weighs in at maybe 15 - 16 stone. I guess that translates to approx. 900 lb - feet of torque.

 

The engine didn't budge!

 

So, I guess we did employ a scaffold tube!

[Tony Millward]

Glad you got that sorted Frank...Agatha Christie would have been proud of that story, I thoroughly enjoyed reading the posts. I put it down to too much air in your offside rear tyre..just shows how wrong you can be eh?....

 

Tony