MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

TR parts and Triumph parts, TR bits, Triumph Car Spares and accessories are available for TR2, TR3, TR3A, TR4, TR4A, TR5, TR6, TR7, TR8, Spitfire and Stag and other TR models are available from British car spares and parts company LBCarCo.

Triumph TR6 - What have I done?

Hi all, I have a problem I can't get my head round and hope somebody can throw some light on. I replaced the thrust washers and while I was there I replaced the main bearings,I was going to remove the oil pump and loosened the three bolts but decided to just remove the pick up pipe and I retightened the three pump bolts but I did not torque them as my wrench does not go that low.After I reasembled everything and put in new oil I started her up and to my horror smoke from the exhaust and blue at that. Oil is entering the exhaust via the valves(Ithink)it is even dripping out of the exhaust joints.The plugs are not fouled with oil and she fired up and sounded ok. Somehow the sump is pressurised and the oil has to go somewhere but why? Basically all I have done is thrust washers and mains bearings.I have now removed the oil pump and it seems ok.I am now stumped as what to do next.Any theories most welcome.
b Wallbank

By the way my name is Barry, sorry about that it must be the stress.
Cheers Barry.
b Wallbank

Hello Barry,

If you remove the oil filler cap do you have a ton of crankcase pressure?

The way to get crankcase pressure is to have a ring set screwed up or something similar. If we allow pressure in the crankcase then you'll have the symptoms you describe. It would be difficult, I think, for valve seal issue to cause the crankcase pressure you're experiencing. For the exhaust to fill with oil then we're into something very interesting.

Did you do the top end?

Jim
Jim Deatsch

Hi Barry

Don't run the car!!!!!

Do you have the outside oil feed to head?

Think you may have a bearing shell wrong way round bottom and top. If one of your oil holes is blocked you have all oil pressure to top end? Outside oil feeder will make worse. Likely the rear shell.

Sorry

Bill
Bill Brayford

GEESSS Bill...you are sure full of good news:)
If you are correct you just saved another...good job Doc!

I am curious though...please explain how the external oil feed makes worse....too much oil to top??
Rick C
Rick Crawford

HI GUYS,I have checked the shells and they are installed the correct way round and I have not touched the top end with no external top end oil feeder fitted ( they steal oil from the crank).There was a dent in the oil pump pick up mesh, maybe the pump was sucking instead of pumping as I forgot to prime it after loosening the three bolts,if that sounds like I am clutching at straws you would be right,I have also checked out the pressure relief valve so I am still non the wiser.


Barry.
b Wallbank

Hi Barry

If your pressurising the sump your oil gage should read zero? If you now have gage pressure. And runs ok, have you let it run long enough to burn off oil? May have just been a prime issue.

Pull your valve cover and plugs. Cover the fenders etc. Have someone crank the engine for a minute with plugs out it should turn fast enough to show what end is pumping too much oil or non if your blow theory fits? Be carefull you may get a geyser? If you have normal even slop you should be ok.

Neat this is 2 oil problems Charlie and Barry same scenario but opposite problem sort of?

Reading several manuals they state its a non drain back type? Both of you have removed or loosened bottom plate only which would allow drain.. Some of the old Americans needed the pump grease packed to prime otherwise they pumped air. This may be the case?

Hey RickC many years ago 60s doing bottom end on a Rambler wagon. Different oil path but close. I was laying on my back dark cold garage and managed to put some shells in wrong. Thing was pumping most oil to top end. Literaly blew out air breather. Pump pumps and it has to go somewhere as Barry says. External oil feed gives it a real good option...:)

Let us know what you find Barry. 2 cases this is getting interesting.

Bill

Bill Brayford

Hi Bill,I think you may be right with the oil pressure being ok I did not run it long enough to burn off the excess oil.I will now remove the exhaust system and stand it up for a couple of days to drain out the excess oil,prime the pump with vasaline,refit the sump and hope for the best.I will have to find a quiet country lane to run her as I don't fancy getting
a ticket for polluting the air.I will let you all know how it goes.

Barry.
.

b Wallbank

Hi guys,Depressing news,after all the work over the weekend I ran the 6 to get rid of the excess oil and to my horror she started to blow oil out of the exhaust and to make matters worse could not select first and reverse gear when hot.After nursing back home I checked the end float and I did not even need any tools, she has thrown a washer into the sump, so it looks like there is some unseen damage to the block where the washers fit. A very expensive lesson to learn,CHECK ENDFLOAT regulary.A replacement engine block is far from cheap but washers are.I have already kicked myself several times and Geez am I sore.

Over and out for a long time Barry.
b Wallbank

Barry,
Sorry to hear this awful news...I'm in the midst if replacing my rear thrust washer ( I'm trying the alloy type ) and also my main and connecting rod bearings. Everything is loosened off and waiting for the postie to drop off the parts. My front TW (thrust washer) is in good shape and specs and I will leave it in and replace only the rear..did you check the end float while moving the crank from below ? mine never had any out of spec movement It was my main bearings that are showing copper that prompted all this )(along with a failed oil pump).
I'm curious as to what went wrong before I hopefully fire mine up next week.
If your rear journal is still smooth an shiny with no scoring you may be ok but if you only worked on the bottom end I'm not clear on how the oil is getting into the cylinders..I think there is more than one problem here..anyone else got a thought on this ?
Keep us informed as to what you find.
Charlie
Charlie Ballard

Was my point exactly when I earlier asked if he had done any top end work Charlie.

How does one get such volumes of oil into the exhaust by merely doing bearings and such?

Jim
Jim Deatsch

I could see a scenario when the trust washers fall out and the resulting excessive crank float moves each con rod to the side when the clutch is disengaged. This side movement would not only wreak havoc on the con rod bearings and piston wrist pins, but would also tilt the piston in its bore. This tilting would allow oil to splash up past the piston rings and out the exhaust.

Charlie--I would also recommend you pull the timing cover to check that the crank sprocket and chainwheel are still in-line after your TW replacement. After I did my TW's, I had to shim the crank sprocket to correct for the reduced endfloat.

Rick O.
Rick Orthen

Thanks Rick,
Since my washers are good and in spec I'm replacing the new rear one made to the same size as the old one so I don't think there will be any change at the timing sprocket but I know what you are saying if it was not for my mechanic friend telling me my end float is fine I would probably have done that.
Charlie
Charlie Ballard

Rick, you have hit the nail on the head,I did orignaly have excess end float,if fact I heard them drop into the pan, I thought I might get away with it but alas I didn't,it still beats me why the plugs are not fouled up with oil though.Number 4 end cap now badly damaged so I have no option but to buy a reconditioned block,looks like I'll be walking for a while.Thanks for all the input.

Barry.
b Wallbank

Barry--Sorry to hear of your unfortunate circumstance with the #4 main. Perhaps a competent machine shop can weld filler material in and machine a new surface? I've heard of others doing the same, but the cost may approach that of a good block core.

Good luck, and keep us posted.

May we all remember to check our endfloats frequently!

Rick O.
Rick Orthen

This thread was discussed between 26/03/2004 and 01/04/2004

Triumph TR6 index

This thread is from the archive. The Live Triumph TR6 BBS is active now.