Club 80-90 Forums

we have finally found out where the airleak is on our engine in our T25. The engine idles fine on tickover (it even passed its MOT) and can be revvd but as soon as you put any load on the engine by driving it it miss fires and looses power.
Hubby replaced the carb and the gasket last year - no improvement, then recently changed the inlet manifold seals halfway along the headers - still no improvement. Last week the garage did an engine compression test and found that the l/h cylinder head was down on compression. No. 3 was 100 psi, No.4 was 50 psi. They also said they could hear the leak and hubby reckons he thought there has been some poppin from that side of the engine. They tried re-tightening the head but to no avail. It looks like the head has loosened itself so they reckon the engine needs to come out and the cylinder heads taken off, skimmed and re-assembled. Hubby has suggested that the garage only needs to do the l/h cylinder head as the r/h one is ok. No. 1 cylinder is at 120 psi and No.2 at 100. he reckons that if the r/h cylinder head is ok it is best to leave it well alone.
Any comments?

i would agree with hubby, if 1&2 are OK ,but 3&4 are down ,then its .3&4 that needs doing doing 1&2 is just going to add to the bill. you could inspect 3/4 and depending on the condition of the head, make an informed decision then .i had a cracked on an air cooled changed the one head didn't touch the other and drove all the way to Gibraltar and back over 2 weeks no problems ,hope this helps

thanks - i like the idea of a cheaper option! then i have money to go away camping!!!

get him to look at the valves & seats. if they are ok & not coked up, then there shouldn't be any probs, he needs to be careful though, as the cylinder head bolts are a bit of a weak link to say the least. apparently its to do with them corroding as they pass through the water jacket . hence the need to change the coolant every 2 years, and you can only use the pink stuff ,but i think there's better details in the wiki section, on what specifications of coolant are required. mines got a 1.9 dg ,so I'm not fully up to speed on the 1.6 ,but I'm pretty Shaw the differences are marginal, the more pennies in the camping pot the better. not too bad for me though, i was born with nothing and I'm happy to say Ive still got most of it left.

no water jacket or coolant, Aircooled

Is this an Aircooled engine or watercooled? The CT engine is Aircooled however you seem to state your van is 1985 which is into watercooled territory and certainly out of the CT production lifespan.

If it's a CT engine you have after all then get ready for a possible bill of a new head... CT's are known to eat heads as they run hot and it's possible if it's been run with a fault for some time you could (and it is only a could too!) get a "it's cracked on the sparkplug thread" message coming form the garage...

its def air cooled.
the only water is in the kettle! (or the passenger footwell after rain

the van is 1980, sorry if i have put the wrong date somewhere.

no worries pal ,if its air cooled then no worry on the coolant corrosion side. i agree with dugcati on the head replacement though. you used to be able to get them repaired, depending on the severity of the damage but that was years ago. now it would probably cost more than a new head . might be worth checking the tinwear on that side though to make sure nones gone astray

Just spotted - the goof was mine as I looked at the van age on one of the other posters to this thread! (durr!)

bear in mind if you do need a new head that beetle heads fit these engines (different length spark plugs though and different amount of cooling fins too) and could be enough to get you out of a jam.... that said if you go for a s/h bug head then you could end up in the same situation!

Lastly -be VERY weary of reconditioned heads as there has been a few people suffering from helicoil'd plug holes that have stripped or caused the head to crack around this area after a bit of use and they had to fork out again for more heads/replacement engine's - sometime he who pays cheap pays several times



If push comes to shove..I 'might' have a spare head I could help you out with but what condition it's in I cant say without pulling it off the lump it's bolted onto

just got back from the garage. The valve seats could do with a reface on both cylinder heads so no.1 head has to come off anyway to get all the valve seats reground. Apparently we should have 130+ psi, we only have 100 on no.1 and no.4 and 120 on no. 2 (no.3 is 50 psi hence the original problems) and the mechanic reckons he can see light passed a couple of them.
Next problem is getting hold of a 1600ct gasket set - nobody seems to have any in stock. As a bare minimum we need the compression rings, exhaust gaskets, heat exchanger gaskets. Does anything else fit the ct engine (like the beetle 1600 bits)?
Any possible leads welcome as we are getting desperate.

As mentioned - a lot of late Aircooled beetle bits fit the CT's, also have a rummage on JK as they do (or did) gasket sets

Doug

Hello happy CT lover!!

Right here goes, Beetle gasket set is what you use on a CT, but there are 2 important differences. Push rod tube oil seals are larger at one end, available JK. Do not lose, destroy, give to the dog to play with the rubber seal under the oil filler breather. They have a fragile plastic bit too, so be careful when dismantling.

From experience I use German quality gasket set, (Serial Kombi) at about 28€, as I consider my time more valuable than filing out milk bottle top gaskets to fit, saving 12€.

Re spacer top and bottom of cylinders. If you have standard beetle barrels and cylinder heads there is no need for them. The head inserts were to allow the use of lower octane fuel. Do use the paper cylinder base gaskets .

Grinding in the valves is normal beetle.

Lap the tops of the cylinders into their respective heads.

Unless you are really masochistic, leave the hydraulic lifters in place, do not alter the settings on the rocker arms.
When you restart the engine, it will clatter a bit. Once run up and then allowed to cool overnight, back off the adjusters 2 turns to do the compression test. 150 psi or 10bars is your goal, but 120 all round is quite acceptable.

Then reset as per haynes.


That should keep you pointed in the right direction!!

Cordialement,

Beetle heads do fit and are £170 from Vw heritage, but they only fit if you change the piston and barrels fro Beetle spec ones too, I know this from a very costly mistake. Heritage also do all the gaskets you need. They do also still have some proper CT heads in stock as well.

I found Vw heritage to be very helpful. if there are any signs of cracks its well worth replacing the heads.

Good luck with it, I;ve just gone through hell and back with my CT lump

many thanks one and all.


lots of useful info.

have found a super mechanic in luton who sorted it all for me. i'll just check with him before posting his details on here. pm me of you need to know.