Mopar Muscle Association UK

Take the rocker covers off and look for tell tail oil leaks on the basket face. I had one at the rear of the rocker where you couldn't see it. I had to use gasket seal to get it right but the leak stopped.

Good luck with this one. Should be a minor fix I imagine. Blues idea sounds completely plausible and, as he has had exactly the same issue you are having and has posted the solution, I would be very tempted to try that first if it was my car. Petes idea is very easy to check as well....nice and simple!

Sure you will sort it in no time at all.

We laugh about the glass of wine scenario but, when I am struggling or getting frustrated, I always take a break (sometimes overnight), have a read and a think (and a beer usually!) then back on it the next day with a fresh head. Always better the next day.

Good luck and please keep us posted

Cheers Steve

Blue wrote:A problem I have found with cast covers on small blocks is they often hit the intake manifold and therefore don't seal correctly. Have a close look at where they pass the intake runners. if you can't see a definite gap then chances are there's no clearance. If the intake was coming off you could grind that for clearance, otherwise grind the covers or double up the gaskets by evo sticking 2 together before you fit them. I had this problem on both my 318 and 408 with 3 different makes of cast cover and 4 different intakes so it's clearly commonplace.

I had this issue and resolved it as Blue says by stacking two sets of rocker cover gaskets rather than attack anything with the grinder. I used rubber gaskets stuck to the covers with a second set of Cometic gaskets which I bought from Turnip as they were a good thickness giving the necessary clearance between intake and valve covers.

Blue wrote:A problem I have found with cast covers on small blocks is they often hit the intake manifold and therefore don't seal correctly. Have a close look at where they pass the intake runners. if you can't see a definite gap then chances are there's no clearance. If the intake was coming off you could grind that for clearance, otherwise grind the covers or double up the gaskets by evo sticking 2 together before you fit them. I had this problem on both my 318 and 408 with 3 different makes of cast cover and 4 different intakes so it's clearly commonplace.

..... so it appears that Blue has found something that I never would've and I would have gone mad trying !!!
Eliminated the PCV, Eliminated the dipstick and took a look at how the rocker covers were sitting compared to the intake manifold and as far as I can see, they are snug up - meaning that no matter how tight the rocker covers are turned down, there is always a chance they are now not compressing correctly ...... to say I'm feeling better is an understatement - now to go about fixing the problem ....
Can anyone point me in the direction of a suitable set of gaskets for my 340 ??
Should it turn out to be correct that they were leaking, do I discard the old ones or can I use them in the "sandwich"
Thanks Garp

Great result!! Very pleased you are sorted! I bet you that almost everything that can go wrong with our cars has been dealt with by someone on here at some point or other

Rocker gaskets should be available from WASP , USAutomotive or Real Steel.

I only just caught this thread and my first thought was rocker gaskets with the amount of oil on there, but obviously the great minds beat me to it!

MattH wrote:Rocker gaskets should be available from WASP , USAutomotive or Real Steel.

I only just caught this thread and my first thought was rocker gaskets with the amount of oil on there, but obviously the great minds beat me to it!

Just sooooo happy everyone agrees on this - makes it far more likely to be the case.
Will try WASP
Cheers mate

I do remember reading about having to have the PCV valve on one side of the engine rather than the other, possibly the engine internals rotation creates more pressure to one side of the engine inside. I think Dave Robson mentioned about it.

Yes, Dave did post on that issue some years ago.

PCV on driver side,filler and breather pass side is what I've always been told.

There should be a diagram in the workshop manual that shows the circulation within the engine and location of PCV etc just to be 100% sure....mine is the opposite to Latils...filler and breather drivers side...PCV pass side (LHD).

Cheers Steve

I got double thickness gaskets for my 360. They weren't dear and saved a lot of pi55ing about sticking two together.
Now, if I could only remember where I got 'em...


Either WASP or Jegs I'm sure.

Steve wrote:There should be a diagram in the workshop manual that shows the circulation within the engine and location of PCV etc just to be 100% sure....mine is the opposite to Latils...filler and breather drivers side...PCV pass side (LHD).

Cheers Steve

OK, so now you got me all thinking again - my 340 has filler only on drivers side, PCV and ANOTHER filler passenger side - no breather at all .....
can I exchange on of the filler caps for a breather (standalone airfilter type as there in no connection to my main air filter) ??
Cannot do any harm I suppose ?
Also, has anyone else with a 340 got their PCV on the drivers side ?If so, when I change gaskets and sort my leak, I will switch rocker covers ... If its good at lowering pressure inside the top half , I'm all for it
please comment if you know something relevant here as I'm all ears.
Thanks
garp

Big Block and Small block Mopar motors rotate in different directions dont forget so the pcv etc should be on different sides depending on what you have

Good point John....mine is big block