exhaust fumes in cab

[steve the tree]

I have recently purchased a 1981 2l air cooled camper and am having trouble with exhaust fumes getting into the cab via heating ducts. Any feedback welcome. Thanks. Steve The Tree

[mrhutch]

heating to the front of the van is provided by heat exchangers that wrap around the exhaust manifolds at the rear. Hot exhaust pipes then heat the air in the exchangers which is blown up to the cab. Rotten heat exchangers can let exhaust gases into the hot air heating pipes and get pumped into the cab.

prolly the exchangers are shot, they are readilly available through JK and others.. can be pricey through.

[Rozzo]

this can also be caused by oil leaking onto the exchangers and finding its way inside them. have a look to make sure they're not covered in oil

[highlander]

you want to get that sorted out pretty quick!!! exhaust fumes are very dangerous and can have a very fast and unoticable effect!! before you know it you are unconcious.... Happened to a mate of mine..... he was very lucky!!!!

[orangebooboobearcrew]

Hi,

We are having the same problem with exhaust fumes in the cab on our 1980 2.0l Aircooled. Just ordered 2 * replacement heat exchangers but interested in Rozzo's point about oil leaking into exchangers. Our exchangers are covered in oil - any ideas where this would normally be leaking from, previously changed rocker cover gaskets but oiled up again in no time and looking at it yesterday, looks like leak may be above rockers? Don't want to ruin a new set of exchangers, especially when they cost £350 for the pair!!!

Many thanks,

Chris

[Rozzo]

if you have new exchangers coming you can prevent the oil smoke by making sure they are completely sealed where all the pipes enter/exit the outer skin whilst they are new and before you fit them. seal them up completely either by using exhaust sealing paste or even better by getting your friendly local welder to seal them properly from new.

[orangebooboobearcrew]

Great - thanks for the tip. I will try this when they arrive. Does this mean the oil leak is normal? (sorry, don't mean to hijack this thread!)...

[ginge]

pushrod tubes tend to leak and drip onto the heat exchangers causes fumes to enter the cab you should be able to shut the heater pods manually if cable is broke that should stop the fumes the pods are on both sides higher up than the heat exchangers they control the flow of air as to say

[orangebooboobearcrew]

I've manually wired the pods open to try and get what little bit of heat I can out of the exchangers into the cab so wiring them shut isn't really an option at this time of year. Is it possible to stop the pushrods leaking?

[steve the tree]

new push rod tube seals should stop the leaks-cheap to buy and not too difficult to fit, you will probably have to reset the valves after.

[jason k]

new push rod tube seals should stop the leaks-cheap to buy and not too difficult to fit, you will probably have to reset the valves after.

ummm at the risk of being condemned here,
i have never reset the tappets after doing the pushrod tubs and never had a problem.

the way i see it is

the motor hasnt turned over or moved, everything has been bolted back where it came from so whats the need??

push rod tube seals are pence
jobs about an hour a side

look carefully at (or take a pic of) the retaining wire before you remove as its easily put on wrongly.

other than that its a piece of pee to do!!!

[Rozzo]

new push rod tube seals should stop the leaks-cheap to buy and not too difficult to fit, you will probably have to reset the valves after.

ummm at the risk of being condemned here,
i have never reset the tappets after doing the pushrod tubs and never had a problem.

the way i see it is

the motor hasnt turned over or moved, everything has been bolted back where it came from so whats the need??

push rod tube seals are pence
jobs about an hour a side

look carefully at (or take a pic of) the retaining wire before you remove as its easily put on wrongly.

other than that its a piece of pee to do!!!

absolutely correct since on the Aircooled you dont have to remove the heads to do the job, therefore the length for the pushrod doesn't change. thats my understanding anyhow

[highlander]

new push rod tube seals should stop the leaks-cheap to buy and not too difficult to fit, you will probably have to reset the valves after.

ummm at the risk of being condemned here,
i have never reset the tappets after doing the pushrod tubs and never had a problem.

the way i see it is

the motor hasnt turned over or moved, everything has been bolted back where it came from so whats the need??

push rod tube seals are pence
jobs about an hour a side

look carefully at (or take a pic of) the retaining wire before you remove as its easily put on wrongly.

other than that its a piece of pee to do!!!

absolutely correct since on the Aircooled you dont have to remove the heads to do the job, therefore the length for the pushrod doesn't change. thats my understanding anyhow

Everybody has there own way of doing it but i would recommend to undo the tappet screws to let of the pressure when removing the rockers, it stops the rocker coming of at an angle and rubbing against the thread and causing damage, it is also advisable to not have any pressure on the rockers for when you torque them back up they only need 18lbs, any pressure from the lifters and rods can affect this and there is also the danger of stripping the rocker shaft studs if the pressure is too much, i have come across some very soft rocker shaft studs!!!

Apart from that just like everyone else is saying it is a simple job even the 2 minutes to reset the tappets is a doddle with the hydraulic lifters, with solids you have to set the gaps to 0.006

[steve the tree]

many thanks for all the feedback . I have replaced the push rod tube seals as they were leaking onto the exchangers and was hoping that this would cure the fault; we're still getting fumes but maybe thats just the residue from the leaks-perhaps I should take the heat exchangers off and see if they are full of oil? is there any way to check the exchangers are rotten before splashing out on a new set and probably other related bits as well. thanks.
Steve Tree

[jason k]

clean em off with gunk and take it for a drive, it will smell till all the old oil has gone.......