TonyB Posted January 28, 2002 Share Posted January 28, 2002 I know there have been several previous threads on this topic but hopefully someone can give me inspiration before I pull the engine out. I have a 1500cc pre crossflow Cosworth Mk IX engine that is blowing significant amounts of oil out of the breather and dipstick hole when reved up. It also "smokes" immediately the engine is started. Engine was rebuilt in 1990 and I installed it "fresh from the crate" a few months ago and have only run it for less than 5 miles due to the oil spillage. Compression (hot with throttles open) are all 150 pounds plus or minus 5 pounds. I have also tested "wet" with no improvement. I have tested for combustion fumes in the water, negative, so no blown head gasket into waterways. Oil pressure is 45 pounds tickeover, 65 pounds reved up (high pressure pump fitted). Any ideas?? Regards Tony Bates SB 1761 - 1963 Lotus Super Seven Cosworth 1500 Link to comment Share on other sites More sharing options...
cdg Posted January 28, 2002 Share Posted January 28, 2002 This may not be caused by excessive crankcase pressure. Compression seems pretty good to me, so I doubt that you're losing much past the rings. I have seen this phenomenen before on quite a few occasions. If you're running an electric pump, but using a camshaft with the fuel pump lobe still on,(most race cams have it ground off) oil can be squirted from the lobe straight up the breather/oil separator.Fuel pump cover plates are available that incorporate a deflector to stop this happening. If your dipstick is in the front timing chain cover,as per the original pre-x-flow Kent engines, you may also be getting an effective splash feed up the dipstick hole! Make sure the dipstick still has the little plastic or rubber grommet still attached, and that it forms a good seal in the top of the tube. Of course it may not be any of these things, but it's worth checking before you go to the trouble of removing your engine. Chris. Link to comment Share on other sites More sharing options...
hardtail Posted January 28, 2002 Share Posted January 28, 2002 my limited mechanical knowledge would lead me to think that you have worn valve guides, you describe the same symptomes i had with my cooper 's', the smoke only lasted a few moments until it burnt off the oil which had settled on the valves when the engine was last used. maybe! Link to comment Share on other sites More sharing options...
TonyB Posted January 29, 2002 Author Share Posted January 29, 2002 Hi All, Hardtail - The smoke I refered to was from the breather not the exhaust so I assume the valve seals are not the culprit. Cdg - thanks for the input, you may have hit on sonething, yes I am running an electric fuel pump and the block just has a flat cover plate with no deflector. Any idea where I might be able to get one with the deflector? Re the dipstick, yes it is in the original position and "no" it doesn't have a plastic grommet on it to stop any spray, again, where would I get one? Regards Tony Link to comment Share on other sites More sharing options...
cdg Posted January 29, 2002 Share Posted January 29, 2002 Tony, You may have to just use a rubber grommet from a DIY/Motor Spares shop for the dip-stick tube. Cant see them being available from Ford! The deflector plate may be available from Rally Design if my memory serves me correctly. Failing that, it would be a simple job to weld a deflector piece on to your existing plate, making sure to clear the rotating camshaft. Sorry I can't be more specific. I will do some checking around and get back to you. Regards, Chris. Edited by - cdg on 29 Jan 2002 11:56:50 Link to comment Share on other sites More sharing options...
John Posted January 29, 2002 Share Posted January 29, 2002 The symptons that you are describing could also be down to oil windage from the sump being too shallow and the crank whipping in the oil. Have you checked that the sump has the correct amount of oil for it? John Link to comment Share on other sites More sharing options...
TonyB Posted January 29, 2002 Author Share Posted January 29, 2002 John - The sump is the "standard" one for a 1500cc Ford 116E, but I may have overfilled it, I'll check when I get back home at the weekend Chris - who/where are Rally Design? Do you have a URL or telephone as I live in California. Regards Tony Link to comment Share on other sites More sharing options...
cdg Posted January 30, 2002 Share Posted January 30, 2002 Tony, There's an engine builder on the US West Coast that specialises in Ford Kent engines. Bob Yarwood. I can't remember his exact location, but his email address is; yarwoodeng@earthlink.net he may be able to help with a deflector plate. I have a pre x-flow dipstick in my garage which uses a valve stem seal for a tube seal. Worth a try! Will dig out Rally Design contact no. for you asap. Regards, Chris. Link to comment Share on other sites More sharing options...
martynr Posted January 30, 2002 Share Posted January 30, 2002 Rally design web address: www.raldes.co.uk Link to comment Share on other sites More sharing options...
TonyB Posted January 31, 2002 Author Share Posted January 31, 2002 Hi guys, Tried contacting Bob Yarwood and Rally Design, no response to emails in either case. Regards Tony Bates Link to comment Share on other sites More sharing options...
TonyB Posted February 2, 2002 Author Share Posted February 2, 2002 OK all, I checked my oil level, it's not overfilled, so it's not that causing the oil escape from the breather, it must be blow by. I tested the compression, all within + or - 5 lbs of 150lbs. Squirted oil in the cylinders and hey presto, + or - 210lbs. The engine was crated for 10 years after a complete rebuild, so either the rings in every cylinder are broken or not seated, but probably not just worn out from old age. Hoping that it's just "not sealed" rings, is there any way I can help the rings to seal without a strip down? Regards Tony Bates SB 1761 Link to comment Share on other sites More sharing options...
Roger King Posted February 2, 2002 Share Posted February 2, 2002 Tony, From your original question, is it correct to assume that you have a breather in the block and one in the rocker cover (usually the filler cap itself)? If there is no block breather, this could be your problem. If it turns out to be rings, the only acceptable way to deal with the problem is to strip the engine, hone the bores and fit new rings. Bore finish is an exact science and is absolutely critical to engine performance and longevity. It is not sufficient just to use 'honing stones' in a big drill, but this is still done by a lot of engine builders. Unfortunately, there is not much difference to see between a good and a bad finish - it's all down to the appearance at a microscopic level. I am of course, assuming that there is at least a decent crosshatch finish to be seen when I say that there is not much difference in appearance; even now we still see bores that have been honed round and round. Now that I've stated the technically correct position, I am going to reveal something that brings me great shame to admit, but just might help. In the dim and distant past a very well respected racing engine manufacturer used to suffer from the occasional case of rings not bedding in and suffering from blow-by. On more than one occasion, Ajax scouring powder was puffed sparingly into the ram pipes in order to get the bedding in process started (Ajax being a very fine abrasive). On some occasions it worked! This can not be recommended and I urge you not to try it. But of course, if you were resigned to stripping the engine anyway, you might feel that it was worth a go, mightn't you? I take no responsibility whatsoever if anyone is foolish enough to try this! Link to comment Share on other sites More sharing options...
Roger King Posted February 2, 2002 Share Posted February 2, 2002 Whoops, double post. Edited by - roger king on 2 Feb 2002 22:34:20 Link to comment Share on other sites More sharing options...
oilyhands Posted February 3, 2002 Share Posted February 3, 2002 Got to disagree with RK on use of AJAX, it was always VIM as any fule no.. I have seen VIM used for bedding rings on glazed bores with varying degrees of success, one on a re-ring job on an Twin-cam Anglia in the wilds of Norfolk overnight between special stages. That one worked well. I have had much success using Flex-hones which give just the right plateau finish if used correctly to hone the bore. Oily Link to comment Share on other sites More sharing options...
TonyB Posted February 3, 2002 Author Share Posted February 3, 2002 Hi Roger and all, Yes, I took everyone's advice (and pulled the top and bottom off and lifted the pistons. To my amazement they are all perfect!! So are the cylinders, you can still see the honing marks. So, it appears that the rings didn't seat. To summarize the problem, Cosworth Mk 9 Ford 1500 pre crossflow with significant amounts of oil blowing out of the block breather. The compression was all within + or - 5 lbs of 150lbs but when I squirted oil in the cylinders and hey presto, + or - 5 lbs of 210lbs. I know I only ran a few miles with the engine but it was "spewing" 1/2 pint of oil per mile out of the breather. So what do I do now? Do I fit new rings (Dyke top ring, solid 2nd and traditional oil ring), do I re-hone the cylinders, help.......! Regards Tony Link to comment Share on other sites More sharing options...
kenny. Posted February 3, 2002 Share Posted February 3, 2002 Please forgive me if I'm talking utter crap, but on my previous couple of x/flow engines years ago I had similar trauma around the block breather area. I was advised to fit a "competition block breather" which I sourced from Burtons ( this was a machined ali. knock in straight through unit) which was piped to rocker cover near filler. An additional output pipe was brazed on to opposite end of cover which went to catch tank on bulkhead. This sorted all oil leaks around the breather area and caught any excess oil that did escape.......might be totally different on yours but I thought I'd mention it to see what the lads think........good luck. Kenny Link to comment Share on other sites More sharing options...
TonyB Posted February 3, 2002 Author Share Posted February 3, 2002 Hi Kenny, Your not talking crap, I have seen advice from both Roger King and James Whiting suggesting plumbing the breather into the rocker cover and then feeing the cover into the catch tank. I will do this on the rebuild. I just felt that "pumping" a pint of oil out of the breather for every two miles driven was not a good indication. Any suggestions regaring re-honing the block, in-situ with the crank still in? Regards Tony Link to comment Share on other sites More sharing options...
cdg Posted February 3, 2002 Share Posted February 3, 2002 Tony, Leave the crank in ??!! I'm not at all suggesting you do this, but crikey!... we've rehoned blocks between races with the pistons still in! Chris. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now