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Hi, I have an engine problem which I can't figure out and I am hoping someone out there has come across this before.

History, I have virtualy reconned the engine (2.5 PI) except the bores were honed and new rings put in, everything else reconned including an unleaded head conversion. The car has done btween 250-300 miles and, with exception of a couple of injector blockages, has run well.

The problem, I set off for a run as usual with the engine runniing well, after about 10 miles I will attempt to go up a steep hill and the engine starts to burn oil. This was on a dual carriage way where I was holding 70mph. The car then burns lots of oil until I reach my destination, usualy not much farther (5 - 10 miles). I used from the top oil dip stick mark to the bottom mark in 5 - 10 miles. You can imagine how please the cars coming up behind me were. I then left the car for about 1.5 hours and set off again, after putting in more oil. The same thing happens again. However if I do not exceed 50mph I use very little oil. When the engine is cold the oil pressure is up around 70psi, when warmed up and at 50-70mph I get 40-50psi but when warmed up, on tick over, the oil pressure is only just regestering. The oil pump is new. I rebuilt the engine myself so I wondering if I have done something stupid. I have heard that the engines use more oil when running in but not this much surely?

 

Regards

 

Peter

 

 

 

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First of all is the dipstick the right one? How much oil went in? It should hold 9 UK pints I think.

 

Secondly, where did you get the oil pump? There have been a few threads on here concerning duff pumps from the Far East.

 

Thirdly is the oil pressure relief valve known to be good? It might be sticking on.

 

Other will be along, soon.

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"The engine burns oil" Do you say this because you have a plume of blue smoke behind? Or just because it's disappearing?

 

Have you bedded the rings? After a new engine start, hold at 3K for twenty minutes to settle to the camshaft, varying it +/- 500.

Then take it out and hard accelerate to a legal speed, then foot off and coast on engine braking, until you wnat to speed up again, don't bog.

This first forces the rings against the bore, then sucks more oil up into them, to ensure that the bores do not get glazed and form a poor seal.

 

Try removing the oil filler cap while the engine runs - is there a mighty wind coming out? That would mean poor ring sealing. A breeze is normal. And where does your crankcase vent go? Into the intake manifold, or into the atmosphere? Is the blue plume coming out of there?

 

Have you fitted an external cylinder head oil supply? This Spawne of Ye Deville not only starves the main, it can flood so much oil into the rocker cover that it gets down the valve guides, but not usually in that quantity, especially if you had new guides.

 

Did you centre the rear crankshaft oil seal? That could be losing oil without burning it, especially on steep uphill slopes! But you would see it dripping out of the bell housing drain hole. Can we presume that you car isn't "marking it's territory", so no external oil leak? The timing cover is another favourite place.

 

 

That makes a a whole lot of ideas to look at, from everyone here. Hope you can sort it!

JOhn

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Hi All, some answers to questions:,-

 

Yes, I did gap the rings before I assembled.

Just did a compression test, all cylinders 200 psi +/- 10psi

The dip stick 'look' correct, but it came with the engine so not sure.

The oil pump was supplied by Barrum Engineering who did the reconditioning, not sure where it was soursed but will find out on Monday (they did tell me when they did the engine that they only use good quality parts, but I can't confirm that)

Oil pressure relief valve is new, supplied and fitted by CRW.

I put in Carstol 20/50 oil, Up to the top mark on the dip stick. I put in roughly a gallon can and roughly another half, so seems about right.

Crank Case Breather??? Is that the pipe which comes out of the rocker cover? If so, because I have K & N filters, it just goes to air.

When I say the engine burns oil, I get large plumes of bright blue smoke from the exhaust. There is also a small amount of blue smoke coming from the rocker cover breather.

I have not done any of the things you suggest to 'bed in' the rings. I have just driven the car for about 250-300 mile so far making sure not to overrev.

The front and back seals were replaced when I rebuit the engine so, although not completly drip free, its very slight.

All plugs are black (carbon, not oil) when I took them out.

 

Regards

 

Peter

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If you're burning oil in that quantity at least one plug must be oily. Valve stem o-rings? And have you staggered the rings ?

Edited by Geko
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Was the engine built by you or by a third party? It's not clear from your post as several outfits seem to have been involved. The oil pressure is worrying on a newly built engine. Do you have a spin on filter conversion and if so does it have a spring boss?

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The engine was mached by Barum Eng. They also did the unleaded conversion. I rebuit the engine. The engine only burns oil under heavy load, does this mean valve stem seals?

The oil filter does have a spin on conversion, done before I got the car.

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The engine only burns oil under heavy load, does this mean valve stem seals?

could be as well as the type of guides used after unleaded conversion

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Valve guides usually show themselves up after a period of overrun followed by acceleration which burns the oil sucked down the guides during overrun. To burn as much as you describe through the guides they would have to be seriously at fault. There are no stem seals.

 

Getting back to the oil pressure, was it OK before the rebuild? Either way I'd have the filter adapter off the block and check that the centre section is spring loaded.

Edited by peejay4A
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I put in Carstol 20/50 oil, Up to the top mark on the dip stick. I put in roughly a gallon can and roughly another half, so seems about right.

Crank Case Breather??? Is that the pipe which comes out of the rocker cover? If so, because I have K & N filters, it just goes to air.

When I say the engine burns oil, I get large plumes of bright blue smoke from the exhaust. There is also a small amount of blue smoke coming from the rocker cover breather.

I have not done any of the things you suggest to 'bed in' the rings.

 

Regards

 

Peter

Thats waaaay toooo mch oil. Sump capacity on TR6 is 1 gallon, 1.1 with an oil filter to fill. So you are using half gallon too much.

What's happening is when you go up that hill the oil level is getting on top of the rear cam followers and being flung in large quantities up onto the rocker platform. And then out ontothe air filters and around the top of the inlet valve stems where it gets sucked back into the engine and burned.

So. Drain the sump, add 1 gallon, put your own mark on the dipstick. Check the oil pressure when driving.

 

Peter

(It could be a saloon dipstick, those enginesare canted over).

Edited by Peter Cobbold
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I know it was a long time ago, but when I was at school a gallon and a half was 12 and a half pints, ..... are you sure you are not just putting too much oil in?

Cheers Rob

Rob, You beat me to it, by a minute!!

 

And Davidw by three hours.

 

 

Peter

Edited by Peter Cobbold
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OK, estimate on how much oil I put in may have been off, but I went by the top mark on the dip stick. I only ever fill to the top mark. I will drain and refill.

Dont go by the dipstick, just add a full gallon can.

Peter

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