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blow by oil

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tahoe healey

tahoe healey

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I know this has been addressed before but I'm getting oil in the rear air filter (BJ8). Enough that it has dripped out onto the brake master cyl (thought it was the cause of the fluid on the floor at first). Can I just plug the line at the "T"? I beleive the rocker is putting out too much oil under the "T" but every thing seems fine and runs well. I know a rebuild is down the road but I was hoping not until after driving season. This happened on the way home from the Dixon show driving in 95+ degrees. (The show was great with probably 200+ LBC's of which about 30 were Healeys including a silverstone(?)with the spare tire serving as a rear bumper). Many Forum folks there. Nice to put a face to the usernames.
Thanks
 
I suspect that ALL of the rockers are putting out too much oil. Plugging the line at the tee will create a LOT of crankcase pressure & make everything else leak. If you just can't have the car down very long, you can probably get a complete rebuilt assembly & exchange it. Check around a bit. https://www.rockerarms.com/

I guess you "could" divert the carb end of the hose into a catch can, but it wouldn't be very pleasant.
D
 
Well TH, if the rockers are not spurting out oil, you might check how deep the "T" is screwed into the valve cover,if set to close to the baffle inside it may act just like a siphon.---FWIW---Keoke
 
It has been suggested that the hose from the "T" to the carb air filter is too short and straight and that there should ba a dip to trap the oil. Sounds like an eventual problem anyway but has anyone heard of this? Should there be a dip in the line?
 
Should there be a dip in the line? --- /ubbthreads/images/graemlins/nonod.gifTH,Keoke
 
There shouldn't be any oil in the line in the first place. Unless the rings are leaking a bunch of compression, or worn rocker arms are flooding the top of the engine. The vent to the carb is mainly to let a small amount of air out, not oil.

There is an off chance that the baffle under the T vent in the cover is missing. Pull the T out & have a look.
D
 
Hi TH, for some reason you have a large positive pressure in the crankcase.This can be abated by installing a PCV valve in the crankcase vent line.I have not set one up on a Healey engine but Norman Knock has and you might give him a call. The PCV valve inverts the pressure in the crankcase ---FWIW---Keoke
One more thought.If you have the original hose on the crankcase vent line it may be resricting air flow.Replace it with a hose from a Volvo P1800E Auxilliary air regulator hose. this hose will make the short top hose and the curved bottom one.It is presaped with a 90 degree bend to use at the bottom and the remainder will be used for the short top piece.Cost is about $10.00
 
Very good points! I do not remember seeing a baffle under the T. Also the hose from the crankcase has the original clamps and are probably the originals. These are easy things to check and I was going to recheck the amount of oil being pumped via the rockers anyway so I'll look for a baffle. If it's not there I guess I'll have to make one since I don't see any in my parts catalog. How can I find out what it looks like?
I see that the rocker shaft is available alone. (I'm guessing that it is the part that is worn.) British Car Specialist have a hardened version. Will that really make a difference? What else needs replacing? Is it better to get the whole pre-assembled (rebuilt)unit?
Thanks for all your advice.
 
Hi TH,
If you don’t want to tackle a rocker rebuild yourself I’ve had good experience with Rocker Arm Specialists . They’ll rebuild yours for about $200. I bought one of their higher ratio roller rocker assemblies. It looks like a piece of art (to a gearhead anyway). I still have my old cover in the garage. If you are baffleless I can get some dimensions for you.
 
/ubbthreads/images/graemlins/iagree.gifWith Greg on the rebuild source.It is best to have the entire assy rebuilt rather than trying to do it at home.The baffel is located inside the valve cover and sits directly under the "T".It is just a small welded on bit that is open only on one side. Make sure it is not bent when you check it---Keoke
 
Has anyone put the PVC valve in and can supply a picture? Also, which PVC valve is used?

I have rebuilt rockers and engine and still get some oil into the rear carb.

Jerry
 
Jerry, I think Norman Knock has a Tech article that defines the correct PCV Valve and the method of installation.---Keoke
 
Many years ago, my BJ8 had the same problem. In my case, the
car ran great and had no problems at all around town or on
short trips. Longer trips at high speeds, and I got oil
in the aircleaner to the point that it would foul plugs.
The problem was worn rocker arm bushings AND a worn rocker
shaft. Replace both (lesson I learned the hard way). Whats
happening is oil is being pumped into the valve cover
via the worn bushings faster than it can drain back into the engine. I did investigate excessive crankcase pressure
(blowby) but that wasn't the problem.

Steve
 
Took valve cover off. Oil now shoots up 10 to 12 inches out of the bad rocker arm right under the "T". The pipes from the botom of the block were very clear. There fore I'm sending teh rocker assembly to the Rocker Arm Specialist on Tuesday. They will use a hardened shaft. Why do these wear out so fast? I only have 50,000 miles.
Thanks for all the help.
 
[ QUOTE ]
Why do these wear out so fast? I only have 50,000 miles.
Thanks for all the help.

[/ QUOTE ]
Knowing the previous source, your speedo could well have 150,000 miles. (A sort of joke) I don't have an answer. It is hard to know the complete history of an engine. It seems that a lot of folks have trouble with worn rocker arms, but the ones without trouble are not often heard from. I've not had any trouble myself.
D
 
[ QUOTE ]
I used a Chevy 6 cylinder from the 60's.

[/ QUOTE ]
/ubbthreads/images/graemlins/savewave.gif
Very interesting was it a direct bolt on??? ---Keoke
 
Just a follow up on the rocker arm. I sent it to the Rocker Arm Specialist (thanks, Dave)last Tuesday afternoon. It came back last Friday (hardened shaft). Installed Saturday. It is great. Oil just dribbles from the rockers. No oil comming through. Price was 25% less than original quote. I'm happy!!!
 
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