very dissapointing oil leak after rebuild.

[theiceman]

well at least after a rebuild its easy to see where its leaking .......

I have oil dripping on to the passenger exchanger towards the outside of the car. ( on my newly blasted and painted exchangers )



got under with my flashlight and took a look . I can see it leaking down from either between the seal or on the edge of the seal where the heads meet the cam housing . I can see and feel the shiny oil as it runs and drips off the orange sealant where it squeezed out.

I guess it could be an upper rocker shaft but I seriously doubt it as the area is supposed to be sealed from that anyway . The housing is supposed to sealed to the heads right across but I will check that out.

I am wondering if I disrupted the seal torqueing the assembly down on to the head studs ( I preassembled the housing to the heads and popped the whole thing on. )


so now it looks like the engine is coming back out.

But I was thinking of just doing it on my engine dolly.

1. drop the engine and remove tin.
2. remove timing cover and undo tensioner and sprocket.
3. unhook chain from cam
4. remove cam housing/ timing box cover plate
5. remove screws fastening shroud to housing
6. back off all rocker arm adjustment screws.
7. unbolt housing and remove with cam still inside .
8.repair seaing surface.


Does this seem like a reasonable approach or am I missing something obvious. ?

Thank s

[theiceman]

a pic of where I see the oil dripping from ( this is of course the before pic of my housing. )

[bigel]

Oh man, I am sorry about that, Iceman...how long post startup did you notice the leak? I thought I was out of the woods, but maybe not.

I started my '87 for the first time yesterday, at which point it promptly developed a tear in the T fuel line. So, I'm not finished just yet.

Hang in there, man.

[kirkf]

Are you using synthetic oil?
Try changing to regular 20w50 oil, and see if you still have a leak.


Regards,

Kirk

[arbita1]

What did you use to mate the two surfaces together.

Sorry...missed the orange description in your original post. Guess it was 574.

I'm assuming the surfaces were clean when you sealed them...not like in the photo.

Sent from my iPhone using Tapatalk

[DRACO A5OG]

Open the valve covers and check the rocker shaft ports for leaks.

[theiceman]

Yeah it was 574. Started leaking about half a tank in.
Was clinically clean even after the machine shop cleaned it cleaned it again with alcohol
Strangely enough I was not sure if have enough so on the other side i put
Yama bond 4 which is basically 1104 and its bone dry.
It's rotella but oil type should mAke no difference in a rebuilt engine anyway.

I seriously doubt the leak being where it is its a rocket shaft but il do my due dilligence obviously
Il try to get a pic later and post
What a bummer.

[Casey at Pelican Parts]

+1 on checking the rocker shafts! You can remove the valve covers and see if the oil is running out of the rocker shafts. EDIT: If this is the case... you do not need to disassemble the engine to reseal the shafts.

We are working on a tech article which will show an upgrade to the rocker shafts, as well as re-sealing them.

[theiceman]

Thanks Casey

I put RSR seals in during my build but of course I will check it out. yeah im thinking an hour if its just a rocker shat , as oppose to a week or two .

wish me luck all

[DRACO A5OG]

Break a Leg Brother.

[prschmn]

My sympathies Iceman. Hate to say it but your plan won't quite work-theres a pair of nuts
inaccessible under the cams. Checking rocker shafts first is wise but if the leak isn't there
you know what you have to do. What I have seen more than once is people forget that
two of the studs must have sealant all the way around them-they are inside the valve cover
whereas two are not. Not that obvious at a glance. All fits with that famous quote==
"experience=that which you get just after you need it"

[VW 612 RS]

Just some thoughts.
You don´t say anything about assembly order.
Could this problem be solved if you mount the cam housing on the cylinder head first and then mount the cam housing preassembled with all three cylinder heads to the engine?

[Walt Fricke]

VW - if his problem is that somehow there was no sealant in a small area which needs sealant, how would the assembly order make any difference?

Me, I like to put the heads on, then the cam carrier, unless I have taken the whole shebang off as a unit to deal with some issue suspected deeper down. That whole assembly is a bit heavy assembled.

I'm betting on the rocker shafts. Oil in the space which is occupied by the spark plug up top, and would have a spark plug if twin plugged down below, can get to that area, can it not? Where oil drips off is often not where it came from.

[dap930]

I had a leak in that area that I wiped up for years because I thought it was leaking from the cam carrier/head joint. Then I had to take the engine out for a clutch replacement. I decided to adjust the valves using the backside method. I found that one of the lower rocker arm shafts had broken at the slot where RSR seals are installed. Of course the rockers was leaking into the lower spark plug chamber (my engine is twin plugged). When I replaced the rocker and reinstalled the engine, I have not had a leak in that area since.

[Casey at Pelican Parts]

Originally Posted by dap930

I had a leak in that area that I wiped up for years because I thought it was leaking from the cam carrier/head joint. Then I had to take the engine out for a clutch replacement. I decided to adjust the valves using the backside method. I found that one of the lower rocker arm shafts had broken at the slot where RSR seals are installed. Of course the rockers was leaking into the lower spark plug chamber (my engine is twin plugged). When I replaced the rocker and reinstalled the engine, I have not had a leak in that area since.

EXCELLENT point! I had forgotten that, but have also seen a crack in the shaft itself cause that leak...

[911 Rod]

I feel your pain Clive

[theiceman]

Okay guys have an update .. first things first checking the rocker shafts. Decided to check the uppe first as that is just half an hour ..

couple pics attached for discussion .
.










one of the upper shafts looks like it has moved slightly has it not ? I put it in flush and now it is sticking out

On the other side I have a blowup of rockershaft. The head of the bolt was definitely wet. When I look closer could that be a piece of an RSR seal poking out ? not quite sitting properly ?

the part I don't understand is how it leaks down if I sealed right across the cam housing.

But anyway thoughts are appreciated from the more experienced.

I will check the lowers next but I want to go for a drive first to se if maybe this fixed it. Fingers crossed.

[boosted79]

I know you aren't "supposed" to do this. Clean with brake kleen until absolutely no oil, then get a q-tip, a dental mirror and threebond 1104. Don't get it in the hex's.

[JJK78-951]

Originally Posted by boosted79

I know you aren't "supposed" to do this. Clean with brake kleen until absolutely no oil, then get a q-tip, a dental mirror and threebond 1104. Don't get it in the hex's.

Wow that looks like a terrible idea.

[theiceman]

okay boys i have an update. ...
went for a nice long drive yesterday and when i got out of car i knew it wasnt fixed immediately all 911 drivers know that smell.

so i jacked up the passenger side today and got under, took off the cover and started examining. All looked bone dry the mirror i was using was a little big and couldnt quite get all the angles.. so i went for my dental mirror and flashlight

..... and sure enough there it was ... a very small but telling pool of oil at the base of the head of the bolt for number 6 ( way to go Walt )
it would have been easy to miss but it was definitely there. .. now this is where it gets interesting.

got my shortened 8mm in place beside the oil cooler and it got the bolt off with a little patience.. bolt came and collars came out, rocker moved easily, and is always a relief.

went to slide rocker out and it stops dead at the edge of the housing .wtf ?

tried a few times and stops dead. go in the house wash my hands ..and vo back in and i feel the tiniest of burs on the housing.. i allmost thought i was imaging it . sure enough it was there got some very fine emery paper and smoothed it out . cleaned it up and shaft pops out.

once out i did a much closer inspection.
rough area of corrosion on the outer edge of the shaft i never saw initially.. piece of the rsr seal missing where i must have caught the burr seen easily with a magnifying glass

as i didnt have another shaft i was able to buff the edge with my buffing wheel i must admit i did put a tiny bead of yamabond with a toothpick around the rsr seal as i did not have another before sliding it into place. cant even see it.

so we have a few suspects whether it be the cut seal, the rough edge on the shaft or a combination

the location i saw the oil trickle (rear side of head on cylinder 6 as in earlier photo) lines up perfectly with the problem i saw so here is hoping.

if i was to do the rebuild again i would use new rocker shafts without question they are not expensive and can prevent headaches.
i still might go back in and replace them all next spring

i will report back

thanks for all the support so far.