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Triumph TR6 - TR6 Engine no hope?
|I just discovered the BBS, lots of great discussion. My pressing question is on the engine for my 1969 TR6. The thrust bearings are shot, they haven't fallen out, but the crank is worn (where it presses on the thrust bearing) and there is some wear on the bearing end cap. I understand that this is a common problem. Is the block and crank junk or can they be saved?|
First off what you see as discussion here is (understatement) just the tip of the iceberg. Join this forum and you will see at the top a new heading called Archive (you do not see it now). The Archive(s) is this BBS back to '98.
Also something you might be interested in is the TR6CD (current thread). I am sending a copy to Moe B. today and he has said he will send a copy to someone else. Contact me by e-mail (remove the "at" and ".dot" from my e-mail) and I will send your e-mail address to Moe.
Paul how did you determine the crank face is worn? Did you measure your end float and how much was it? I presume you dropped the pan and pulled the rear end cap.....a little Deja Vu here...:)
I just went through this process you mention. UUUMMMM.... how to give you the bad news gently....but then the good news.
If you pulled the end cap then you have a journal bearing in hand...what does it look like? More important is what does the bearing surface on the crank look like? You might get lucky here. Most likely the bearings need replacement if it (all of them ) are OE. What is mileage on engine?
Hope you are sitting down "cause here it comes...
I was going to replace my crank bearings and thrust washers..I had 18THOU end float (should be 4 to 8THOU). Not sure how you would have crank wear from the thrust washers since you say they have not fallen out YET. By the way, I would not drive the car till you fix this or YES the block and crank will be toast! OK..so if you have a worn crank then you should really have the crank turned..are sitting down? This means the engine needs to be pulled and stripped down. When I saw my crank bearing surface it had 2 2THOU grooves in it and simple needed to be turned down 10 THOU. Engine pulled, stripped, crank turned, rebuilt. I am just finishing off putting her back in now.
Sorry, forgot to say NO your engine is not junk by any stretch of the imagination. As said, it will be though if you do not address this NOW!
Paul, if you respond back to this post then I will continue to help and give you info on where to get better than OE thrust washers and VP2 quality bearings.
The answers to my questions will help to see if the crank needs to come out. There are others who have gotten away with just bearings and thrust washers replacement with engine still in the car.
An important question is what is your end float?
|Driving the car is not an issue as it is many pieces right now. This is a long term frame off restoration and the engine is upside down on a stand in my garage. I am not sure as to the mileage on the engine. I have not measured the end float, other than it is substantial, I have removed the bearing cap that retains the thrust bearing so I know it was still there and not in the pan. That said the bearing cap has grooves on it and so does the bearing face on the crack. The bearing surfaces (to my eye) look on. There also does not appear to have been any crank to block contact other than at the one bearing cap. I am assuming that the bottom end will at a minimum will need a rework. I am assuming that what I need is a shop that is familiar with this type of problem or advice as to what to ask the shop to do.|
|P A Smith|
|Rick, I think you have to assume "the current set" of thrust bearings hadn't fallen out yet. And Paul, I suspect your car had the thrust bearings replaced, but the previous owner didn't go all the way to ensure a lasting repair. Good thing you saw the problem in the shop, not on the road.|
Excuse delay in posting back was busy getting my 6 ready for start up. Had successful fire up on Sat. morning. Ya' gotta' love seeing the oil pressure gauge going up to just under 100 Lbs. Only one minor leak in the oil pan gasket but think it might correct itself as I was able to tighten pan bolts a little more after she warmed up.
Well you are in a VERY good position to do major work on your engine. NOW is time to do it. We are slightly different in when we discovered our same problems...yours was out of the car my engine was in the car:) A lot of work to re and re an engine.
My "project" I bought in pieces..kinda like a kit car that comes in boxes:) I finished my body off restore back in '01 and was told there had been work done on the engine. My DPO just did not mention that the work done was the replacement of a piston and rod that had broke but did not go through the block. Another piston (#2) had #1 ring and the metal between #1 and #2 compression rings broken. I was real lucky in that the "floating" pieces of metal did not score the wall at all. Not sure how long this situation was going on.
Anyway, Paul I do not say I am an "engine guy" but now have an experience with a TR6 engine. I would think the chaps who really know our engines might elaborate here.
"I have not measured the end float, other than it is substantial, I have removed the bearing cap that retains the thrust bearing so I know it was still there and not in the pan." I am not trying to be smart here Paul but there are 2 thrust washers ...You use the singular venacular...maybe you did a typo. You use the word "substantial" and mention.."That said the bearing cap has grooves on it and so does the bearing face on the crack."....Substantial..grooves on the cap...maybe you have not done a typo....but your first post you use plural??? So the question of the day is...did you find 1 or 2 thrust washers? There is one either side of #4 main journal. This will be interesting to hear your answer.
If your crank thrust washer bearing surface (most likely the front face) and #4 main cap are "grooved"...well...look for a thrust washer on the engine front side of this journal. Like I said, question of the day..Is there one there?
Regardless of answer, you will need to have the crank turned to repair the thrust washer surface. The main cap maybe an issue. It should not touch the crank at all on its edges. Does the #4 main crank cap bearing show wear/scores on is edge (not face)? If you had "substantial" crank walk then maybe you might want to look at the other three main caps edges. I would look at the con-rod bearings...very easy to look at. If all your bearings are OE they will be stamped with : MAINS: 149550..A4 STD AV. CON-RODS: S2022SA...STD G/A TB...149549. These are VP2 standard bearings and are most likely OE to the engine. The STD means non over sized bearings and COULD say the crank has ever been turned. If you see .010 stamped on the bearing(s) well your crank has been turned. The OE thickness of Thrust Washers was .090" each. What do (yours) measure? To some degree end float measurement is irrelevant as you will need to replace the washers and your thickness needs can only be determined at time of "how much" is being taken off the crank. End float spec is 4 to 8 thou. There is a supplier of "better than new" thrust washers in the US who will make washers done to the .001" increments. My 2 new TWs are a STD .090 and a .098 giving me a measured 4 thou end float..YA HO BABY! I also know where to buy OE quality VP2 crank bearings. Both suppliers are on the CD.
I paid (and quoted): Crank turn .010 $82.00. Thrust was not needed to be turned ($72.00). Straighten not needed ($28.00) and HOT TANK dip the block $100.00. Also since I needed to replace one main cap, line bore $250.00. So my cost was $432.00++ I put another $200 cash on the table and he virtually redid my head, installed ALL bearings,(I paid for them $100.00), installed the crank, and installed pistons (new rings $57.00) then head. He threw in the block paint job and the cylinder deglazing. I also did new tappets($40.00) and push rods($32.00) and upper and lower gasket set(s) ($36.00) Timing chain and tensioner ($14.00..YES 14 dollars) Front and rear oil seals ($6.00) and the most expensive was the core plug set at a whopping $4.97..:) ...cam was in perfect shape. I bought a rod bushing set ($10.00) but mine just needed a little cleaning so have available for free to first offer to to pay shipping in Canada...not worth it for someone in the US as it would cost more for shipping:) Also 2 thrust washers ($35.00) and used #4 main cap and piston $100.00.
Total: $1057.00 a mix of $US and $CDN.
Sorry got a little carried away but info for you Paul as to what it would cost you to redo the engine. I would add another $1000 for the head rebuild including parts. I have heard a non do it yourself engine rebuild for $2500 to $3500 from TR6 experts.
Your crank can easily be taken to a shop for examination. Consider just $CDN82.00 to have it turned plus $72.00 for the thrust turn then new bearings are the same price regardless of STD or .010" over.
Finally , it is MUCH easier to rebuild your engine now than to have to pull it out and do it later....MUCH easier:) Since you have excessive end float it is time to redo the engine.
Sorry Paul, I did get carried away here with a reply but hope this helps you.
Hey Rick...you are quick. Glad to hear your engine is up and running well. You must have really hustled to get it back together.
I got mine fired up last Monday evening. I have since put about 10 miles on it (weather hasn't been great). It's a nice strong engine now. Great oil pressure. No oil leaks (not yet anyway) and no coolant leaks. All okay so far. Hope it stays that way.
|HP Henry Patterson|
|Rick, thanks for all the info. You seem to have this acquired a lot of knowledge (experience?) during your rebuild. Both washers are there, the inner washer does not look hardly worn, the problem washer is the outer. This is typical, I believe, due the thrust from the clutch bearing on the outer washer only. The outer washer has worn to the point where at the extreme of travel the crank is meeting the outer end cap. How the washers have not fallen out is a mystery, there is certainly enough clearance for them to fall out. Really, that they have not fallen out is a bit moot as there is damage in any case. I take it from your post that a good engine shop will be able to rework the crank as needed. What concerns me is how much material can be removed from the thrust washer surface before i) The crank is too weak in the area, ii) The thrust washer required is too fat requiring a custom washer ?. I am assuming that in almost all cases the wear is on the outer thrust washer surface and that the inner surface (and therefore the inner thrust washer) sees little if any wear.|
|P A Smith|
|I am in the process of building my first TR6 engine although I have built several small block chevys and fords. Is the process of installing a full circle of thrust washer (two) on the rear of the main a good idea or a must do idea. Is it needed at all?|
The Thrust Washers are a must...without you will end up with a heavy boat anchor. The 2 only thrust washers are a "C" shape and only sit on the top side of that main bearing of the crank. Have fun:)
Paul Yes you are correct it is the outer that gets the wear...oops. The crank is heavy "beefy" enough to have a litlle removed there. It is your #4 main cap you should be concerened with. Scott does the "custom" sizes of washers..like I said in .001" increments. If you get just one faced turned then you want a standard .090" one and then the outer one will be what you have now for end float plus what the engine builder will remove. OE thrust washers are .090"x2= .180 thou. Quite frankly I would also replace the inner one...now is the easy time to do it:)
Check out this link:
25. http://users.arczip.com/zntech1/tr6.html Scott Helms BETTER thrust washers.
This was taken directly from the CD. Also for US parts and the VP2 bearings. I found even with exchange and shipping, the prices are better south of the border.
21: http://www.bpnorthwest.com/.sc/ms/hm/1104328695745765/9/nc/ee TR6 Supplier VP2 (Vandervell) King brand bearings. Be carefull their WEB page just shows the standard Below is link to the VP2 set. Have fun..away on business for week and half so will post back then.
I think Gene is asking if he makes a modificaton to be able to use two full circles of thrust washers on both sides of the crank rather than the standard 1/2 circles on both sides...would it be worth it.
Is that right Gene?
I have never heard of anyone doing that. I have heard of some people permanently attaching the thrust by pinning them to the cap.
|HP Henry Patterson|
|I thought I had heard of someone doing that by machining the cap for it. It seems to be a good idea except that I don't want to reinvent the wheel if someone has done that. Seems 2 half circles on the thrust side (flywheel) would be better than the stock one.|
|I believe I have also heard about someone doing machine work to install a full 360 thrust washer. That is something I am interested in. Hopefully someone will be able to post an answer to this.|
|In my rebuild the thrust washers were pinned and I believe a new oiling port was added at the back washer. But that is fuzzy memory!|
|I also saw something on this but cannot locate it now. Perhaps someone can use the web-page wayback machine (the site that archives deleted pages) to find the post.|
|Henry & Gene,|
Never heard about full circle TWs. IMHO I do not think it is necessary. The OE ones are to be replaced at around 50,000 miles. With Scott's special TWs you will probably get more miles. I do not know about you, but I dought I will put 50K miles on my 6.
Henry, I am home for the weekend so hopefully I can get my 6 off the blocks and go for a short ride.
|When's that first mile?|
See new thread :-(
This thread was discussed between 27/04/2005 and 08/05/2005
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