over heating 1.6 Aircooled

Post by **wrexhamwrecker** » 27 Oct 2008, 07:42

hi i have a 1980 1.6 t25 twin carb man tappets keeps getting hot and closing the tappets what would be the best thing to do? it only has 2000 miles on the clock had the engine rebuilt as it was the oringal ct unit . should i put an electric fan in the enginebay if so what one?
thanks
si

Post by **cumbriankeith** » 27 Oct 2008, 10:31

Your engine is likely to have hydraulic tappets (aka lifters or followers) so therefore do not need clearance - they are preloaded. It is possible that the original lifters have been replaced with solids during a rebuild but you need to find that out. Does your "man tappets" mean you know they are not hydraulic?

From the wiki - a great source of info about our vans:
CT 1,6l 4-cyl. Flat4 air-cooled 79 to 82, 37Kw / 50bhp
Loosely based around the type 1 VW engine with added hydraulic tappets, removable spin on type oil filter, cooling fan on end of crank. Very under powered at 50hp, but quite economical. Watch out for cracked cylinder heads as these thing eat them, make sure thermostat is opening as if it isn't then your looking at a cooked engine.

To adjust them:
Position engine at TDC and slacken rocker nut on No1 cylinder, undo screw until it is no longer contacting rocker and then screw back in 'til it just makes contact with rocker. Now tighten 1 further turn and tighten locknut. Repeat for cylinders 2,3 and 4 by turning engine a half turn (distributor rotor will move by 90 degrees) in an anti clockwise direction.

Post by **wrexhamwrecker** » 27 Oct 2008, 18:15

thanks Keith mine are not hydralic tappets they where taken out in rebuild

Post by **cumbriankeith** » 27 Oct 2008, 18:20

6 thou clearance is standard for these engines.
Steve Shaw is not far from you and knows everything - might be worth a call/visit? http://www.gasure.co.uk
He's a busy man tho...

Post by **wrexhamwrecker** » 27 Oct 2008, 18:33

i know the clearence but its he overheating that closes them up
thanks

Post by **VWCamperfan** » 27 Oct 2008, 18:49

These engines have hydraulic tappets as standard so i'm guessing yours have been changed.
Check timing isn't too far advanced and that your fuel mixture isn't too lean, both of these will cause overheating.
Check your air flaps are opening as these not only cool the engine but also the oil cooler.

Post by **wrexhamwrecker** » 27 Oct 2008, 18:52

Hi mark yes been changed my engine builder hates them lol
will try what you say thanks
and what oil cooler?
Si

Post by **VWCamperfan** » 27 Oct 2008, 19:39

Theres an oil cooler on the top left hand side of the engine as you look at it from the back. Its under the engine tinware but the right hand end is visable. Its held to the top of the engine with three nuts which do up on three studs protruding from the top of the crankcase.
It is possible that the airways through this cooler have become blocked and no cooling air is flowing through it, although this is unlikely after such a short mileage on the engine after a rebuild.

Post by **Laurie** » 27 Oct 2008, 20:11

If the cool.ing flaps are not fitted, the engine will overheat badly. No direc ted air to the cooler.
Also, is all the tin fitted correctly and the surround seal?

Post by **wrexhamwrecker** » 27 Oct 2008, 20:29

thanks every one will tinker around with bits and bobs see what happens
Si