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Me too, huge improvement.
RGP
I do no think it would matter if you effectively converted the OEM system to what Vancouver and I have done; but without the catch can. I can see not reason why you should not just modify the tubes in the B bank air box backing plate, so that there is a continuous path (ie tube) from the inlet from the pig's snout out to the tubes that go to the manifolds, and, here is the best bit, just remove that daft spring-loaded valve thingy.
You would get good suction at tickover, progressively less at wider throttle openings, just like our catch cans provide. FYI after about 18 months my CC had about 3mm in it, so not needed on a Jaguar V12!
I honestly can't say why I haven't done this yet,,, I still have lots to do on the ol girl,,, but while this topic is up, knowing I will be doing it someday, I do have a question. Specifically about routing a tube directly from that 3way steel tubing that goes across the vee to both intakes, leaving the third leg for the pvc, crank case breather set up... it I'm guessing is the suction source folks are using...?
Q: is tooooo much suction and negative pressure (constant) good for the crankcase and it's seals? I guess I've worried about that a bit... That the vac will be toooo high. Should I be? I don't wanna be that WORRY guy, but it's just a que
That plumbing looks FINE.
The Can has NO 3rd port, so GOOD. Some have a 3rd port, with a filter to atmosphere, NOT what you want. The one I just fitted to the X Type came with that, and a plug to seal that opening when used as a Vac style can. Diesels etc use that atmospheric filer for turbo something or other.
The V12 has NO other open port for a huge vac leak by design. So, there is a lot of air getting IN somewhere.
Dipstick seal.
Oil cap seal.
Pig snout is split.
Timing cover access plug is leaking/missing.
Can itself is NOT air tight.
I will keep thinking, but thats all I reckon.
Dipstick is very tight, oil cap seal is new, timing access cover plug is new and in place, pig snout is new and leak free. I verified the catch can is air tight by clamping the inlet then outlet lines in sequence, and both reduce engine rpm. I have a smoke machine so I'll hook it up soon to check for leaks.
Smoke test didn't reveal anything, certainly no big leaks. Did find out that my air cleaner housings leak a lìttle around the filters.
I verified that my AAV is working correctly. Blocking that hose had no effect one the engine is warmed up.
I need to double check that the extra air valve that opens when the AC runs is working correctly. Just thought of that this evening.
Ok, so then the problem is down stream of that. Maybe the connection to the intake or one of the small hoses there. I had a massive hole in one of them that I couldn’t see but eventually found with a finger underneath.
Ok, so then the problem is down stream of that. Maybe the connection to the intake or one of the small hoses there. I had a massive hole in one of them that I couldn’t see but eventually found with a finger underneath.
I took a picture of the stock setup on my 1989 V12. Not sure what year yours is, but I bet there is some type of restrictor in the line - likely in the part attached to the air filter housing. I'll check tomorrow.
The PCV valve in the stock setup causes a slight restriction, not a lot, but some. The air cleaner housing doesn't have any restriction. In fact, the system can draw air from both the crankcase vent, and filtered air from the air cleaner.
The X Type is finally fixed, whoopee. For Sale sign removed.
Clamping that hose from the Pig Snout to the can confirms what you suspected, and proved, its vac tight, as are the other items.
The "air" it is sucking is on the atmospheric/engine side of said clamp, and the items I mentioned, and you have ticked off, are all I can think of that "could" suck atmosphere into the engine,
and then the snout and the can.
That hose clamped, also confirms there are NO odd Vac leaks anywhere else.
I have cast my minds eye, I dont have a V12 here at the moment, and I cannot picture any other atmospheric openings on the thing, so baffled I be.
Release that clamp, and revs rise, so its finding air from somewhere.
A puzzle. I would start by removing the B bank airbox/air filter cover and looking carefully inside the airbox where the welded fitting is that connects the input from the pig's snout/can to the pipes across the V.
Try blocking off the various orifices and see what happens.
Also, can you post more detailed photos of how the hose from the catch can is joined into the Y pipe? I think this may help to be part of the diagnosis.
From this photo you posted earlier:
it seems (but I am obviously not sure) that the CC hose is attached directly to the Y pipe without the OEM PCV valve. Thi raises a couple of questions:
1) if it is not there, then a restriction has been removed from the circuit, which may account for the higher revs? and
2) How did you block off the entries into the airbox?
Another question, what is that other pipe for, the one alongside the Y pipe across the V? That does not exists on the UK spec engines.
Last edited by Greg in France; Sep 25, 2021 at 05:12 AM.
OK, Looking again, and my one remaining eye sees something odd.
The pigsnout TO the CAN< GOOD.
Can to ??? where.
In that snap, it appears to go somewhere other than the end of the pipe that once had the PCV valve in it.
Too many things blocking a clear view of that hose and its connection to the Y pipe.
Sorry, got caught up in other repairs.
Today, while working on the air cleaners, I saw something that may be the whole issue. I had gone thru the whole linkage/throttle plate setup, and somehow I ended up with the throttle valves
not sitting on the stops at idle. I've readjusted the linkage rods, properly this time. The engine is down for other reasons at the moment, but I'm sure that readjustment will help.
Sorry to hijack this thread again.. Can i know what is the ID for the hoses to the oil catch tank?
I do not have my car with me now but would like to order an oil catch can.
Thanks
Mine came with a couple of spigot sizes; but you do need to buy a reducer to fit the pig's snout exit from the cam cover:
This sort of thing will do it, the threaded part just clamps into the snout with a Jubilee clip. https://www.aliexpress.com/item/32796565074.html
Thanks Greg.
I was thinking of something like this
It's transparent, so i will be able to see if there is any oil, and it seems to have outlet at the bottom..
It is cheap, so i will probably buy and try
Originally Posted by Greg in France
Mine came with a couple of spigot sizes; but you do need to buy a reducer to fit the pig's snout exit from the cam cover:
This sort of thing will do it, the threaded part just clamps into the snout with a Jubilee clip. https://www.aliexpress.com/item/32796565074.html
I really enjoy these moments.
