100M starts to drink oil..................

[356roadster]

Just a short report how things are going on concerning my oil problem:

I have connected the tube exiting the side cover with a small bottle to see whether oil is coming out here -> result after 200kms: nearly zero oil in the bottle; just a few drops

Next check: I have connected the baffled vent from the tappet cover with a small bottle, too. -> result: the same, just a few oil drops on the bottom of the bottle

Next thing will be to check whether the tappet cover and the oil sump are sealed perfectly.....

I will report again.

 

[356roadster]

I am starting to run out of ideas.....

I have checked the sump now and have refitted it properly -> no oil leak from this side. I have also removed the oil-pipe near the rear seal which leads into the sump as recommended.

I have mounted a new speedo cable which was the reason for some oil dropping down as the outer cable was damaged -> no oil leaks from this side anymore.

I have checked the tappet cover which seems to be properly mounted as there is no oil coming out.

The containers (fitted by myself) connected with the vents from the valve cover and the side tappet cover does not show any signs of oil in them (only some small amount of oil steam...).

When the engine is running, there does not seem to be any oil dropping at idle speed. When the engine is turned of some drops are exiting from the normal position between engine and gearbox.

There is still no blue smoke from the exhaust and the spark plugs are very light brown (which does not seem bad; maybe the carbs have to be adjusted a little bit more rich..).

But:::::: The oil consumption ist still astronomic: It went down from max to min at the dipstick in only 150mls......

Next thing I will do is to let the engine run at 3000revs for some minutes and check underneath whether I can detect any leaks then....

Do you have other ideas how to proceed?

Thank you very much for your support!!! Wolfgang

 

[healeynut]

Wolfgang -

I am sorry to report to you that Dave Russell is very ill with cancer and is not posting any more to this list. Let's give him our very best prayers, he is very sick - it came on very suddenly.

With respect to your problem, I would have to agree with Dave. I do suspect it is leaking from the rockers into the valves and burning off, even if you don't see the blue smoke.

As long as your spark plugs aren't getting fouled with oil, it's generally ok to drive the car with it burning a little oil. When it starts getting too much, you'll need to take your rocker off and have it rebuilt.

One very important thing - when you remove your rocker, DO NOT remove (and later install) the banjo bolt first. It is better to undo the oil feed pipe at the point where it connects to the cylinder head and then remove the banjo bolt afterward (and more important when installing, install the banjo bolt and oil feed tube to the rocker FIRST, slightly loose, then install the rocker on the head, then finally attach and tighten the oil feed tube to the head). If you don't do things in this order you will strip out the rocker shaft pedestal's oil feed tube attachment threads. Maybe to clarify - when removing the rocker -> the banjo bolt comes out last, when installing the rocker -> the banjo bolt goes on the rocker first before installation.

Good Luck!

 

[356roadster]

Alan -

thank you very much again...

I am very sad to hear about Dave´s health; I hope that there is a good chance for him to get better again. Let us all hope the best for him!

As I am not an engine-specialist I can only follow your recommendation. I am only surprised that such a volume of burned oil cannot be detected or smelled at the exhaust...

I assume that the work can be done without removing the head, right?

I will check for a suitable specialist in southern germany as I have learned from other threads that it is not an easy diy job...

All the best, Wolfgang

 

[glemon]

Wolfgang, I still go back to Dave's comments on oil consumption, a quart of oil or whatever it takes to make the dipstick go from max to min looks like a lot of oil on the floor of your garage or when going up in blue smoke, I had a Tiumph with a very wron motor that smoked in huge obnoxious quantities but I could drive about 300 400 miles before adding a quart, light brown is good for the plugs, if burning a lot they should be more black and sooty looking.

As far as checking the oil, have you tried letting the engine sit for a while before checking, as sometimes more oil settles back into the pan after it sits.

Also is your initial check when full right after an oil change? maybe the filter hasn't filled yet and this makes it go down.

Oil is relatively cheap and the fixes can be expensive, as long as you are keeping things monitored and topped up you can keep driving and monitoring for a while to try to figure it out.

The rear main crank seal would probably empty out into the tranny bell housing, but that oil would have to come out eventually too.

I do like Dave's idea about the black light test, I think he explained it pretty well, but you basically add a little additive to the oil and then using a special light it really stands out or glows as it comes out of the motor.

Do you have access to a lift? being able to stand under the car and check things out can really help as opposed to crawling around on your back and looking.

 

[356roadster]

glemon -

thank you very much for your comments. I already did the black light test and detected an oil loss coming from the speedo (revs) cable (there were quite a lot of drops as long as the engine was running) and I have already fixed this leak. But this was not not the reason for the heavy consumption unfortunately

I was checking the oil level at the dipstick when the engine was cold and the car sitting for a few hours because I also thought that the level should be checked always at the same conditions.

The rear main crank seal is a problem on my car but the volume of drops which eventually come out after stopping the engine is very limited. And - in my opinion - this is normal for the 100 engine.

I have noticed the oil consumption problem for the first time after changing the oil and re-checking the level after a long run. During the oil change I have also changed the oil filter to the modern type (sorry but I do not remember the specifica name for this modern filter version). But I suspect that the oil and filter change can be the reason as I did this shortly after buying the car and I don´t know anything about it´s consumption before.

But coming back to Dave´s advise: Either the oil is burned in the engine or it has to come out somewhere! So what I will do is to let the engine rev at 3000 or so when the car stands still for some minutes and checke whether any significant leaking starts.... I do not have´other ideas.... And if this is not the case (no leaks) I will measure the "data" of the exhaust smoke because - in my opinion - they should be cruel if so much oil is burned, right?? In this case the next step obviously would be to make the rocker assembly repair.....

 

[Michael Oritt]

Wolfgang--

If you do not have a rear seal kit installed or if your rear seal is worn your engine will likely blow more oil out if the oil level is at the "full" mark, and will blow less as it approaches the "fill" mark. Why not let your oil come down to the lower level and see if consumption drops off a bit.

An additional thought--perhaps your dipstick is miscalibrated or is not seating all the way down causing you to overfill the sump. I believe 7 US quarts should fill engine and filter--how much does your car require?

 

[Healey 100]

Friends:

I've read this thread for some time. My Healey has had major oil leaks but usually consumed less than a qt every 400 miles or so.

I had another old car that consumed oil like Wolfgangs, it burned a quart every 150 miles or more. And guess what, almost no smoke at all from this car.

However, when I followed the car I could clearly smell burning oil even though there was little visible smoke.

I eventually learned that engine had many broken rings and ring lands. When I put new pistons and rings in that car, the oil consumption dropped to practically nothing.

I suggest that Wolfgang's car is burning the oil, probably due to bad rings or pistons. Since his leaks are under control, there really is no other credible explanation. Oil is either getting into the cylinders via the rings or through valve guides. The only way to find out for sure is to pull the pistons and look, measure, and renew. And replace the valve seals and rework and magnaflux the head while you are at it. I think if you do this you will cut your oil consumption drastically.

Good luck!

 

[roscoe]

Don't forget about the differential compression test. Any piston engine aircraft shop will have a tester, and you can buy them for from 50 to 150 dollars. You put each cylinder, in turn, at TDC and with the engine warm, put about 80 psi into one cylinder at a time with a spark plug adapter. With the piston at TDC on compression, if there is ring blow by you will hear air hissing our the case vent. If there is valve blow by you will hear it out the intake (carbs) or our the exhaust pipe. The aircraft testers have a calibrated orifice between two pressure gages that allow you to see the amount of leakdown from a fixed input pressure. If you put in 80 psi and can't hold 60 in the cylinder most aircraft people will change a cylinder. It you buy it through an automotive store I'm sure it would come with directions. Really any goo auto shop should have one too.

 

[356roadster]

Michael, healey 100, Jon,

thank you very much for your help and your recommendations. I will have a lot to do during the weekend now..... I am happy to do all things I can manage on my own first. I will need professional help to put off the head and check the pistons. So I will start to check how much oil is transported to the rocker section when the engine is reving higher than idle speed. Dave suggested me to do so earlier but I have only checked this at idle speed yet (my mistake). Maybe I can check this through the oil filler cap in the valve cover?? Dave and others have told me that too much oil in the rocker section could cause my problem. I think that it´s advisable to check this before putting the head of, right?

Wolfgang

 

[RonMacPherson]

Roscoe, no need to have to go to an aircraft shop.

In automotive land this test is called a cylinder leakage test(cylinder leakdown test).

Testers can be found at just about any well equipped auto parts store or tool truck. Or can even be made relatively inexpensively. I consider it a very good test, helping to pinpoint combustion loss.

 

[Healey 100]

Wolfgang:

It is always best to do all the testing you can before pulling the head and pistons, this is a big job. So keep looking for leaks and external causes.

If the oil is not returning to the sump from the rockers, you either have a badly leaking rocker oiling system (this should be visible when running the engine with the rocker cover off) or your crankcase pressure is so high that oil cannot return by gravity to the sump. If the latter is the problem, you will need to renew rings, pistons, and/or bores to fix it.

Good luck
Bill

 

[Michael Oritt]

A leakdown tester will allow you to test the efficiency of each cylinder and might point the way to the source of the oil leak. By removing the rocker arm so that your valves stay closed you can test each cylinder for the condition of the valves as well as the ring seal at various heights in the bore simply by rolling over the engine and testing from TDC to BDC, etc. For example a cylinder wall might be scratched at the bottom and the leak would show as the piston is lowered and tested at say, top, middle and bottom of stroke.

BTW this may be obvious but I always bring the first guage to 100 psi and then crack the valve and read the second guage as a simple percentage. Naturally you want as close to 100% as possible and 90% to 95% is about minimum for a street engine.

 

[glemon]

Ba da bing, I am going to make my guess, because I experienced it on my Healey motor before the rebuild, but maybe not as badly, you are getting blowby from worn rings and bores, which is of course greater at greater RPM, this blows oil out the rear main scroll seal as you go down the road--but not so much leaking at idle or sitting with the engine off.

Anyway as stated by the others a leakdown test, or evne the simpler compression test should tell you something about the sealing capability of your rings and valves.

Bad news is if I am right the motor will need a rebuild eventually...please do note that Road and Track did right about these cars that the motors were low stressed rbust units that tended to increase their tolerences and burn more oil as they wore out, but would go and go even in that state, I drove my 100 for many years with low compression before the rebuild.

 

[356roadster]

Hi there,

just to keep you updated: My next step is to put off the rocker assembly and send the complete unit to Steve at ukhealey.co.uk.

He is offering a complete rebuilt of the assembly at a very reasonable rate and - as I have noticed - it does not seem to be an easy DIY-job, right?

I will come back to you as soon as there are news concerning my problem.....

Best wishes from sunny Bavaria, Wolfgang