gas/diesel hydro lifters?

[truckinwagen]

hey all, trying to rebuild a head for as few $$ as possible.

I have some gasser hydro lifters that I can use, are they the same as diesel ones?
that is, can I install the gasser lifters in a diesel head?

-Owen

[Dakotakid]

Same.

[RabbitJockey]

i think you can use the later mk4 2.0 lifters that are lighter

[truckinwagen]

cool, thanks that will save me a bunch of money.

[Rabbit on Roids]

you dont need light weight lifters in a diesel, you will never spin it enough rpms to see a benefit.

[truckinwagen]

not really looking for the lightweight ones for higher revs, its just that I already have some, so I dont need to buy more.

[RabbitJockey]

yes but i figure if you are replacing them, why not the lighter ones

[subsonic]

I think someone from here who lives out west ran some of the lighter ones a while back and had a lifter failure.  Might have been prothe lifters, not sure.  Was it jimfoo?

[Rabbit on Roids]

yes but i figure if you are replacing them, why not the lighter ones

lighter ones will have less metal, witch in turn means less strength. and ive seen many a VW diesel wiped out from cracked lifters turning sideways and breaking the valve head off, and you guys can guess the rest of the story. anyway, i personally would use the most heavy duty lifter i could get my hands on. last time i tore my 1.5 apart, i ran into a cracked lifter, not broken, but cracked. glad i caught it none the less.

[truckinwagen]

I see no reason that a diesel would put more stress on the lifter than a gasser.

the cracked lifter in your 1.5 would have been a mech one, which can break from having too much lash allowing the cam to smack the shim rather than push it slowly.
hydro lifters, when working right, should not loose contact with the cam, eliminating the problem.

I will probably use the gasser ones as they are fresh, and less likely to stick than the diesel ones coming(which have been sitting for many a year)

I will, however have the diesel ones on hand in case there is some issue with the gasser ones.
and problems with hydro lifters are very apparent, as they are almost always superseded by loud valve tap.

-Owen

[TurboJ]

Do not use the lighter lifters on a diesel engine!  Many engines have had them fail.
The reputable German aftermarket spares manufacturers that make lifters for both gasser and diesel engines have two different parts available - they have different weight. The heavier lifters are 'heavy duty', and they're the ones they recommend on diesel engines.

I can't really explain why the diesel engines require stronger lifters than do the gas engines, but they seem to do. I know of cracked lifters destroying complete heads when the lighter lifters have been used on a diesel engine.

VAG original lifters have the same part number for both gas and diesel engines, however. I believe they only make one but they make it so that it's strong enough for any VAG engine. Makes sense that aftermarket manufacturers make alternative versions so they can sell one cheaper, but if you don't know for sure your lifters are OEM, then make sure they are HD! Otherways it won't look pretty when they crack...

[truckinwagen]

good to hear, but reasons for the lightweight lifter failure would be good too.

as for the lifters I have, they are stock lifters from an 85 GTI, so they should not be the light weight ones.

I just wanted to make sure they were not a different stack height or something.

-Owen

[TurboJ]

OK, there is a theory about this; presumably the 'lightweight' lifters are able to compress the valve springs just by means of oil pressure, on diesel engines. That will occasionally cause the valves to hit the pistons.
This would make sense if you think about it. Diesel engines have softer valve springs, so they may have different requirements for the lifters. The cases I have headr about the head has gone totally, and the eventual destruction has been caused by valves hitting the pistons. So VAG has just one lifter type, but with the aftermarket ones, you should really use HD ones if you have a diesel engine.

[truckinwagen]

cool thanks, that makes alot more sense than the "they are weaker" argument.

its not about their strength at all, but the way they can pump up leaving a valve open.

all of this may be moot(for my build anyway) because it looks like the diesel ones I got will be usable after all.