Oil leaks from 4.2

[eddiecross]

Hi,
The 67 is finally back on the road but I have a couple of persistent oil leaks. At the rear looks like a mains oil seal. At the front either the same or maybe the head/timing cover- I'll do more investigation.
Question is how far I can go to fix the leaks without pulling the engine?

Thx
Eddie

[mtnjag]

Before you pull the engine for the BIG rear crank/main seal job check to make sure it's not a simple rear pan seal. Seals the rear radius of the pan up to the rear main cap. An afternoon under a car on stands you can pull the pan, replace the rear pan seal and have it back up. Or MUCH cheaper at a shop.

Mine was leaking like the Titanic and I thought the same, rear main. Couldn't really tell where it was coming from. Retired Jag mechanic friend told me to try the rear pan seal first since it's quick and easy and could be the issue. It was! Leak fixed. Major work spared.

Front, cam covers often leak and weep down and look like the front seal. It may also be where the pan goes onto the front seal. When you pull the pan, clean well, some Hylamar or the like and back up with the pan. Could fix it.

I used a Cometic Pan Gasket. No sealant on the gasket. Just a couple of tacks of adhesive to hold it up to the eng. No leaks. Neoprene alum sandwich gasket, very good, ck the site.

[eddiecross]

Many thanks for the advice on where to check Layne. Also, I was not sure if I could pull the pan with the engine in.

Regards
Eddie

[mgcjag]

Hi Eddie...re pulling the pan....there are a few threads on how to do it on the forum if you search. .....basically you have to slightly raise the engine so the rear of the pan can clear the reaction plate and get the crankshaft in the correct position.....Steve.......se post 23 viewtopic.php?f=3&t=10590&hilit=Sump+remove&start=20

[mtnjag]

Yes Eddie, really not a bad job on jack stands and if you have access to a lift much better. I did it on stands. My 3.8 is a little easier at the rear I’m told but 4.2 very very doable. As said above, check out the other posts on pulling. Happy to answer any questions I can. One of those posts I contributed to i think.

I would imagine a shop would get you maybe 3 hours on it. Wouldn’t take a pro more time than that regardless of what they say.

[caveman]

I thought my rear main was leaking, turned out to be the rear sump cork gasket, suitably replaced with rubber version and bone dry for last two years:

viewtopic.php?p=135078#p135078

BTW, engine remained in place for sump removal.

[eddiecross]

Thanks all. I now have the info I need.
Really helpful.
Cheers
Eddie

[malcolm]

When you say a "persistent oil leak", how much do you mean? A few spots on the garage floor, or a gusher? You could spend a lot of time (and money) trying to get it leak-free, but small leaks are part and parcel of E Type ownership. The famous Jaguar anti-rust system!

[flatfloor 3.8]

Removing the sump pan is best done with the reaction plate removed. It is possible to wiggle it out with it in but when putting it back on you need to offer it straight upwards to keep the seals and gaskets in the correct position, especially the rear seal, and use Wellseal it is far superior to any other sealer. The Jaguar engine can be made leak free despite what people say, ( for a few years anyway ).

[mtnjag]

I did mine in my 62 without removing the reaction plate no problem.Lifted the rear slightly. Had removed the harmonic balancer but not sure if that was necessary. You do need to have the crank in the correct orientation to enable this to happen.

There are several posts here on the method,I know I posted in one then when I did it.

[44DHR]

As regards removing the Reaction Plate easily, I noticed the video posted in a link from this post. The video is under 3 minutes.
Post #6 in this post has a link to Post #23 in an associated subject from Tony where the video shows a simple process using two dowels to permit the Reaction Plate to be removed while leaving the two torsion bars under tension and “without upsetting the suspension” as Tony states.
It looks a neat and easy way to remove the Reaction Plate, but have many people used this method as it does appear that the Reaction Plate should be removed to ensure the rear seal is cleanly offered up to the rear bearing housing as the sump is refitted.
Regards,
Dave

[mgcjag]

Hi Dave....removeing the reaction plate is nothing new...its detailed in the "engine remove" section of the service manual.....where you just knock the bolts back.......its all easily doable providing no seized bolts etc and ensureing you relieve the tension as described.......also depends on your facilities..lift etc.....i find it far easier to just sepetate the front hubs from the upright (balljoint)..you then have no tension in the torsion bars....then mark the rear splined end so you can refit it back in the same position.....undo the bolts and remove the plate.....no hammering in taper pins or relieving tension....Steve

[mtnjag]

I have read on the various posts regarding pan removal that the 4.2 pan is more difficult to R&R easily without removing the reaction plate than the 3.8 pans. Possible, with reported success on various posts, but more limited access due to pan shape. And since the subject is a 67 we are talking about a 4.2.

However on the 3.8 cars I can report, having done it myself on my back with the car on jack stands, that it is a quite straight forward to R&R the pan with good access to properly locate the seal and offer it up properly without removing the reaction plate. I placed some temporary studs in the block to locate the pan when i replaced it and removed them once other bolts were placed.

Eng crank must be in the correct location which i believe is for the rear rod journals to be in as horizontal a position as is possible. Others here can confirm if i am correct or not on that positioning.

I know there is a post here also that notes how to find that position by measuring the distance of the piston from top of the head that is incorrect and corrected later in the post. But it is relatively simple to establish that position.