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Brian Eldred

Leaking like a sieve

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Hello again gurus,

Having cured the oil leak from the rocker cover nuts of my 4a, the car was running well and we set of on a road trip around south west France. We got back home 12 days ago (via the show at Stratford), having covered 1700 miles. The only issue was that I put 8 litres of oil in :wacko: (and it would take another litre to top up to full). That's about 200 miles/litre. I parked it up and have only just had the enthusiasm to try and do something about it.

I could see that oil was clearly coming out of the dipstick tube. Also some on the rear lip of the rocker cover again. It may have been coming from other places too, but hard to tell as the sump and chassis rails as far back as the rear wheels are covered in oil. There was even an oil mist on the rear bumper and boot lid. So I guess this is a symptom of excess crankcase pressure?

Today I've done a compression test, and get 170, 171, 174 and 170 psi dry, so that looks ok?  The breather system consists of a pipe from the crankcase (fuel pump blanking plate) and another from the rocker cover, both going to a 2l catch tank - see picture. This has been in for over 2 years. I've checked the pipes are clear. 

Interestingly, when I disconnect the breather from the rocker cover with the engine running there is a fair breeze emitted, but I can't feel anything coming from the crankcase breather pipe.

Work I did a couple of months ago was replacing the camshaft, and then replacing the head gasket for the second time after it blew, this time getting the head skimmed. 

So please does anyone have any suggestions or similar experiences? One idea a colleague gave me is that the head gasket could have been faulty and is blowing through to an oilway. I've read on here that a leak down test is probably the next step?

Thanks, BrianIMG_20190828_173924.thumb.jpg.4d4598a4de01d7f3ebf5d21309df956b.jpg

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50 minutes ago, Brian Eldred said:

Hello again gurus,

Having cured the oil leak from the rocker cover nuts of my 4a, the car was running well and we set of on a road trip around south west France. We got back home 12 days ago (via the show at Stratford), having covered 1700 miles. The only issue was that I put 8 litres of oil in :wacko: (and it would take another litre to top up to full). That's about 200 miles/litre. I parked it up and have only just had the enthusiasm to try and do something about it.

I could see that oil was clearly coming out of the dipstick tube. Also some on the rear lip of the rocker cover again. It may have been coming from other places too, but hard to tell as the sump and chassis rails as far back as the rear wheels are covered in oil. There was even an oil mist on the rear bumper and boot lid. So I guess this is a symptom of excess crankcase pressure?

Today I've done a compression test, and get 170, 171, 174 and 170 psi dry, so that looks ok?  The breather system consists of a pipe from the crankcase (fuel pump blanking plate) and another from the rocker cover, both going to a 2l catch tank - see picture. This has been in for over 2 years. I've checked the pipes are clear. 

Interestingly, when I disconnect the breather from the rocker cover with the engine running there is a fair breeze emitted, but I can't feel anything coming from the crankcase breather pipe.

Work I did a couple of months ago was replacing the camshaft, and then replacing the head gasket for the second time after it blew, this time getting the head skimmed. 

So please does anyone have any suggestions or similar experiences? One idea a colleague gave me is that the head gasket could have been faulty and is blowing through to an oilway. I've read on here that a leak down test is probably the next step?

Thanks, BrianIMG_20190828_173924.thumb.jpg.4d4598a4de01d7f3ebf5d21309df956b.jpg

I would remove those K & N mini filters they do not help with the pressurising

I had a similar problem with a new engine removed the filter and end of problem.

Regards

John

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As has been discussed before - are you perhaps just over-filling it?  Some four pot engines (mine included) seem happiest with the oil about half to two-thirds up the dipstick.  Anything more seems to just get thrown out in short time irrespective of engine health. Trying to keep it topped up to the full mark is maybe just throwing oil away.

 

 

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Yes I've read this too, so after it went from full to off the bottom of the dipstick, I just topped it up to half way each time. Kept the speed down too, rarely over 3000 rpm.

Before I did the cam etc I used to run it on or near the full mark with only minor leaks, though haven't done a long run for some time. 

I'll try running without the filters on the catch tank, or maybe just clean them in petrol? They've been on for over 2 years though.

Brian

 

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That setup looks more like a "Negative Crankcase Ventilation" system - essentially a closed system.

The "old" crankcase breather system used just a draft tube that extracted crankcase fumes by negative pressure under the car as it went down the road, with fresh make-up air drawn in through the wire gauze in the old style oil filler cap.

The next evolution had eliminated the draft tube and used engine vacuum through the air cleaners. The oil filler cap has a small, metered  drilling to bring fresh but unfiltered air into the engine.

The last system used the Smiths PCV "mushroom" valve to control the vacuum pressure at the manifold and the same oil filler cap that your car now has, which has the metering hole and also some fine wire for filtration in the little housing on top of the cap.

In your setup there is nothing to create a vacuum to pull the fumes out the crankcase. I would consider installing the Smiths PCV on the manifold, keeping the catch cans and connection to the old breather location, eliminate/plug the valve cover connection and route the top hose from the cans into the PCV. You can then experiment with the air inlets. Either eliminate the two K/N filters and rely on the oil filler cap, making sure that it is clean and not blocked, OR use a TR5/6 unvented oil filler cap and perhaps just one filter on the catch can.

I can't see your air cleaner setup. but you might be able to route the hose now going to the valve cover to the back of one the filters if there is room for a fitting. Or put together something like the factory did, going into both filters from the off side. The catch can will separate out any oil in suspension.

Alternatively install a draft tube eliminating the current lower hose connection to the catch can, leaving the upper hose from the valve cover. Your choices on air intake would be much same as described above, but using the old style big oil filler cap.

TRI-009_2.jpg

Edited by Andy303

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Hi,

Had oil loss as an issue when I first had my TR4, check the forum and many suggested running half way up the stick,

I was topping it up to the top mark as you would..but then lost oil quickly during a run...sometimes down to the bottom mark!

Have run half level since and it more or less stays there and occasionally have to top up 1/2 litre..

Mine had a K&N directly on the rocker cover outlet, removed that and fitted a pipe feeding down past the petrol pump, 

Sound like an expert..but learned it all from the Forum..:D

Nigel.

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17 hours ago, Andy303 said:

That setup looks more like a "Negative Crankcase Ventilation" system - essentially a closed system.

The "old" crankcase breather system used just a draft tube that extracted crankcase fumes by negative pressure under the car as it went down the road, with fresh make-up air drawn in through the wire gauze in the old style oil filler cap.

The next evolution had eliminated the draft tube and used engine vacuum through the air cleaners. The oil filler cap has a small, metered  drilling to bring fresh but unfiltered air into the engine.

The last system used the Smiths PCV "mushroom" valve to control the vacuum pressure at the manifold and the same oil filler cap that your car now has, which has the metering hole and also some fine wire for filtration in the little housing on top of the cap.

In your setup there is nothing to create a vacuum to pull the fumes out the crankcase. I would consider installing the Smiths PCV on the manifold, keeping the catch cans and connection to the old breather location, eliminate/plug the valve cover connection and route the top hose from the cans into the PCV. You can then experiment with the air inlets. Either eliminate the two K/N filters and rely on the oil filler cap, making sure that it is clean and not blocked, OR use a TR5/6 unvented oil filler cap and perhaps just one filter on the catch can.

I can't see your air cleaner setup. but you might be able to route the hose now going to the valve cover to the back of one the filters if there is room for a fitting. Or put together something like the factory did, going into both filters from the off side. The catch can will separate out any oil in suspension.

Alternatively install a draft tube eliminating the current lower hose connection to the catch can, leaving the upper hose from the valve cover. Your choices on air intake would be much same as described above, but using the old style big oil filler cap.

TRI-009_2.jpg

I've got the same oil filler cap as you mention. Whole engine was seriously coked up when I got the car - not sure it had ever had an oil change - oil was as black as midnight, as was the oil filter. The mushroom type valve was completely clogged and after cleaning the engine ran much better - but I was not experiencing any oil loss before. The oil filler cap needed a good soaking in diesel/petrol mix and when I dried it with air line - stuff resembling Horse Hair came out of the top part, maybe this was the fine wire but now disintegrated??? 

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38 minutes ago, rogerowen said:

I've got the same oil filler cap as you mention. Whole engine was seriously coked up when I got the car - not sure it had ever had an oil change - oil was as black as midnight, as was the oil filter. The mushroom type valve was completely clogged and after cleaning the engine ran much better - but I was not experiencing any oil loss before. The oil filler cap needed a good soaking in diesel/petrol mix and when I dried it with air line - stuff resembling Horse Hair came out of the top part, maybe this was the fine wire but now disintegrated??? 

Yes thats the stuff. It could be replaced by steel or brass wool. IMG_2739.JPG.6db8f5f0ef36a2b67cd78189901ee8ef.JPGIMG_2740.JPG.062e78a5894f21d69445c866bd3387a2.JPG

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Thanks for all the suggestions folks. I had the original 4a PCV system, but changed it for the current setup, with an electric fuel pump, 2 1/2 years ago. I decided to do this partly down to the deficiencies in the PCV setup I'd read about on this forum. I've done maybe 2000 miles with this  before experiencing the problems I've had in the last couple of months. So something must have changed?

I still have the PCV, so I will try various configurations to see if there is any improvement. But first I need to clean all the muck off, and put some proper oil in since I've been topping up with 15w40 which is all I could get in France, which doubtless is not helping!

But I still have a basic question: how do I know whether the blow-by in my engine is 'normal' or excessive? Is a 'leak down' test the next step? If so I'll see if my nearby classic-friendly garage can do it.

Brian

 

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On my TR4a, the PO mounted the block mounted breather pipe from a Tr4, and removed the stock Tr4a PCV system (the vent hole on the valve cover is capped). It also has the stock Tr4a oil filler/breather cap. Using this configuration,  I have not had any oil loss issues.

Jim

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6 hours ago, Andy303 said:

Yes thats the stuff. It could be replaced by steel or brass wool. IMG_2739.JPG.6db8f5f0ef36a2b67cd78189901ee8ef.JPGIMG_2740.JPG.062e78a5894f21d69445c866bd3387a2.JPG

Aha, so that top cap comes off? I did not know this. Also -Wife's nag is shedding it's winter coat - so I could replenish with horse hair FOC! But as you say probably better to use steel wool.

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Hi Brian, I have been running a Tr4 crankcase breather pipe in my 4A block and a straight pipe from the rocker cover down past the chassis rail for over 10years. Engine has done 30,000 miles and on a recent t 1400 trip to France used  about 3/4 pint oil.

I think your answer is to determine where all the oil is coming from and ending up.. Assume the catch tank is not full, the underside of car is covered in oil, a small amount could come out the dipstick. What rear crankshaft seal do you have, original scroll or lip seal.  If a lip seal has it failed?      Seems like most of oil is coming out there to end up on chassis.              As already mentioned if your K&N filters on the catch tank cannot pass enough air or have become blocked then you have sealed the engine and the rear crankcase seal is the only way out for the pressure which will take the oil with it.

Maybe your setup could cope with the original engine back pressure but with a bit of engine wear the Ballance has been tipped and now the pressure exceeds the provided means of escape.

Chris

Edited by ChrisR-4A
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Hi Chris,

I don't know what type of crankshaft rear seal I have, nor whether it's leaking. I've ordered an angled lance for my pressure washer, so when that arrives I'll get busy with the gunk and clean everything up as a starting point. Then I'll try running without the filters on the catch tank.

Brian

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22 hours ago, ChrisR-4A said:

Hi Brian, I have been running a Tr4 crankcase breather pipe in my 4A block and a straight pipe from the rocker cover down past the chassis rail for over 10years. Engine has done 30,000 miles and on a recent t 1400 trip to France used  about 3/4 pint oil.

I think your answer is to determine where all the oil is coming from and ending up.. Assume the catch tank is not full, the underside of car is covered in oil, a small amount could come out the dipstick. What rear crankshaft seal do you have, original scroll or lip seal.  If a lip seal has it failed?      Seems like most of oil is coming out there to end up on chassis.              As already mentioned if your K&N filters on the catch tank cannot pass enough air or have become blocked then you have sealed the engine and the rear crankcase seal is the only way out for the pressure which will take the oil with it.

Maybe your setup could cope with the original engine back pressure but with a bit of engine wear the Ballance has been tipped and now the pressure exceeds the provided means of escape.

Chris

I was thinking the same - rear cfankshaft seal>

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If you saw the oily liquid gunge that goes into my catch tank you would be dumping any system that puts it possibly back into the inlet tract via a PCV, inlet manifold or air filters! I have the TR4 block breather system either pushing straight out or into the catch tank & then exiting out (depending on which car) & both rocker covers venting also into the catch tank. (The Racetorations system). I do have leakage from the rear oil seal on one car which is due to the awful original design of crankshaft scroll & weak oil seal. The other car has, I suspect, the 'Mad Marx' type of seal that gives no leaks at all on my car. Frankly the original design of these cars gives huge probability of engine leakage & even rear oil seal (usual cause) replacement can still give leakage unless meticulous replacement & quality improved seal is used.

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An update: I finally got around to cleaning all the muck off and replacing the oil, filling to half way between the dipstick markers.. Then I tried the first suggestion from John of removing the two filters from the catch tank. 

Took it for a run on Sunday, only a thirty mile round trip, but gave it some beans. Result! No oil coming from the dipstick tube, and no noticeable drop in level.

I jacked her up and had a good peer underneath. There is some leakage from the timing cover oil seal, but only a few drops on the cross member. Can't see any from rear crankcase: there is some oil on the gearbox but I think that's a gearbox leak as it took 1 1/2 litres when topped up before I went on my trip. That's another issue!

So I'll try cleaning the filters or replacing with some alternative as it's a bit smelly as is. I'll have a look at how the Racetorations system works. I agree with Monty that I don't want to be directing the gunge that is in my catch tank back into the inlet manifold! Then I'll replace the timing cover seal, which was replaced recently, but I've read another thread on that subject...

Meanwhile I'm going to get my local garage to check the gearbox oil level again and have another good leak inspection. 

Brian

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1 hour ago, Brian Eldred said:

An update: I finally got around to cleaning all the muck off and replacing the oil, filling to half way between the dipstick markers.. Then I tried the first suggestion from John of removing the two filters from the catch tank. 

Took it for a run on Sunday, only a thirty mile round trip, but gave it some beans. Result! No oil coming from the dipstick tube, and no noticeable drop in level.

I jacked her up and had a good peer underneath. There is some leakage from the timing cover oil seal, but only a few drops on the cross member. Can't see any from rear crankcase: there is some oil on the gearbox but I think that's a gearbox leak as it took 1 1/2 litres when topped up before I went on my trip. That's another issue!

So I'll try cleaning the filters or replacing with some alternative as it's a bit smelly as is. I'll have a look at how the Racetorations system works. I agree with Monty that I don't want to be directing the gunge that is in my catch tank back into the inlet manifold! Then I'll replace the timing cover seal, which was replaced recently, but I've read another thread on that subject...

Meanwhile I'm going to get my local garage to check the gearbox oil level again and have another good leak inspection. 

Brian

The Racetorations one is a closed tank with a large pipe coming out and down to the chassis facing backwards so use venturi effect to draw fumes out, Ive been running that on my 4a for years, not a cheap kit but it works very well.http://www.racetorations.co.uk/triumph-c56/tr3-c4/tr3-oil-system-c648/oil-breather-tanks-c650/racetorations-tr2-3a-closed-engine-breather-kit-p143

Stuart.

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1 hour ago, stuart said:

The Racetorations one is a closed tank with a large pipe coming out and down to the chassis facing backwards so use venturi effect to draw fumes out, Ive been running that on my 4a for years, not a cheap kit but it works very well.http://www.racetorations.co.uk/triumph-c56/tr3-c4/tr3-oil-system-c648/oil-breather-tanks-c650/racetorations-tr2-3a-closed-engine-breather-kit-p143

Stuart.

You need negative pressure, either from manifold vacuum or the under chassis venturi effect, to provide proper crankcase ventilation. The catch can captures the "gunk" before it enters the intake (hence the name) though on a high mileage car some fine oily mist might still be draw into the engine.

Stuart: On your TR4A is the draft tube installed in the "old" location in the engine block, or did you blank off the fuel pump and tap into the blanking plate?

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