78 VW Rabbit Diesel New Cylinder Head Leaks Oil In Coolant

I replaced the cylinder head, cylinder head bolts, timing belt,
tensioner, and head gasket on my 78 VW Rabbit Diesel. It runs great,
but now leaks a small quantity of oil into the coolant. I then
replaced the head gasket (again), and applied the torque settings to
the bolts as outlined in the Bentley manual, but it still leaks.

I did not have this problem prior to the head replacement. The
cylinder head is under warranty--my initial assumption is that there
is a problem with this rebuilt head.

Could anyone help me out with some advice on how I should proceed?

Thank you in advance!

Jeff

On Feb 21, 12:17 am, "JH" > wrote:
> I replaced the cylinder head, cylinder head bolts, timing belt,
> tensioner, and head gasket on my 78 VW Rabbit Diesel. It runs great,
> but now leaks a small quantity of oil into the coolant. I then
> replaced the head gasket (again), and applied the torque settings to
> the bolts as outlined in the Bentley manual, but it still leaks.
>
> I did not have this problem prior to the head replacement. The
> cylinder head is under warranty--my initial assumption is that there
> is a problem with this rebuilt head.
>
> Could anyone help me out with some advice on how I should proceed?
>
> Thank you in advance!
>
> Jeff

Did you check the Head & Block for flatness? Most heads are lapped for
flatness to prevent exactly what you are suggesting. And if your block
has not been checked, it too could be out-of-flat. If you have access
to a machinist's rule and some gauging tape, you might be able to
determine (crudely) if your block is OK.

Next: Did you use (or does VW suggest) an oversized headgasket?
Sometimes if the head is milled flat, such is required for proper
piston clearance. Whoever sold you the head should address that
directly.

Next: Are there any cracks in the head or block? You can get a kit to
detect cracks (I believe from VersaChem). Check the head while you are
at it, especially if it was rebuilt and not *brand* new... and even
then.

Next: Last time I did a head, there were also some small O-rings that
needed to go in with the head at some oil channels and so forth. Does
the Rabbit have those? If it is an "old" rabbit, it just might. Did
you perhaps forget one of those?

Next, and please do not take this the wrong way: It makes a difference
as to how the head-bolts are sequenced and torqued, and the degree to
which they are tightened on each pass. I am sure you got this
correct... just asking.

Can you see where the oil is getting through the gasket? There should
be some sort of mark or stain or some such indicating the leak point.

Last: Are you getting an audible *POP* when cold if you were to remove
the radiator cap?

Good luck with it.

Peter Wieck
Wyncote, PA

did you clean out al the block head bolt holes? If not you may have cracked
the block between the oil pressure feed and the head bolt near it. It was
common on the early blocks to crack there even before the engine was taken
apart.


"JH" > wrote in message
ups.com...
>I replaced the cylinder head, cylinder head bolts, timing belt,
> tensioner, and head gasket on my 78 VW Rabbit Diesel. It runs great,
> but now leaks a small quantity of oil into the coolant. I then
> replaced the head gasket (again), and applied the torque settings to
> the bolts as outlined in the Bentley manual, but it still leaks.
>
> I did not have this problem prior to the head replacement. The
> cylinder head is under warranty--my initial assumption is that there
> is a problem with this rebuilt head.
>
> Could anyone help me out with some advice on how I should proceed?
>
> Thank you in advance!
>
> Jeff
>

You cannot use an oversized gasket on a VW diesel. The thickness is
selected based on piston height above the block surface to maintain valve
piston clearance and proper compression. Unfortunately This problem will not
be easy to find. He could be leaking anywhere, the head could be cracked, or
warped. the block bolt holes for the head could be cracked. It could be
anywhere. Even unrelated to the head change. He doesn't say how much its
leaking either. Or what shape the car is in. This could help decide how to
make a repair or find the leak.
"Lost In Space/Woodchuck" > wrote in message
...
> did you clean out al the block head bolt holes? If not you may have
> cracked the block between the oil pressure feed and the head bolt near it.
> It was common on the early blocks to crack there even before the engine
> was taken apart.
>
>
> "JH" > wrote in message
> ups.com...
>>I replaced the cylinder head, cylinder head bolts, timing belt,
>> tensioner, and head gasket on my 78 VW Rabbit Diesel. It runs great,
>> but now leaks a small quantity of oil into the coolant. I then
>> replaced the head gasket (again), and applied the torque settings to
>> the bolts as outlined in the Bentley manual, but it still leaks.
>>
>> I did not have this problem prior to the head replacement. The
>> cylinder head is under warranty--my initial assumption is that there
>> is a problem with this rebuilt head.
>>
>> Could anyone help me out with some advice on how I should proceed?
>>
>> Thank you in advance!
>>
>> Jeff
>>
>
>

BTDT. As far as headgasket thickness you are correct. But did I ever tell
you about my 81 Hi-performance Dasher diesel? Among us techs it was a well
know fact that the early diesel had problems starting in cold weather. I
purchased a diesel for almost nothing because it needed a head due to
warping. I fixed it by having a machine shop "true" the head on a CNC
machine and installed a 1-notch headgasket vs the 2 or 3 it required. Also
lowered the RPM limiter some. The result was an diesel that would run like
a.... well hi-po diesel. It had so much compression it would cold start
without pre-glowing the plugs. Ran it for 2 years then sold it to my friend
who ran it into the ground.


"none2u" > wrote in message
et...
> You cannot use an oversized gasket on a VW diesel. The thickness is
> selected based on piston height above the block surface to maintain valve
> piston clearance and proper compression. Unfortunately This problem will
> not be easy to find. He could be leaking anywhere, the head could be
> cracked, or warped. the block bolt holes for the head could be cracked.
> It could be anywhere. Even unrelated to the head change. He doesn't say
> how much its leaking either. Or what shape the car is in. This could help
> decide how to make a repair or find the leak.
> "Lost In Space/Woodchuck" > wrote in message
> ...
>> did you clean out al the block head bolt holes? If not you may have
>> cracked the block between the oil pressure feed and the head bolt near
>> it. It was common on the early blocks to crack there even before the
>> engine was taken apart.
>>
>>
>> "JH" > wrote in message
>> ups.com...
>>>I replaced the cylinder head, cylinder head bolts, timing belt,
>>> tensioner, and head gasket on my 78 VW Rabbit Diesel. It runs great,
>>> but now leaks a small quantity of oil into the coolant. I then
>>> replaced the head gasket (again), and applied the torque settings to
>>> the bolts as outlined in the Bentley manual, but it still leaks.
>>>
>>> I did not have this problem prior to the head replacement. The
>>> cylinder head is under warranty--my initial assumption is that there
>>> is a problem with this rebuilt head.
>>>
>>> Could anyone help me out with some advice on how I should proceed?
>>>
>>> Thank you in advance!
>>>
>>> Jeff
>>>
>>
>>
>
>

Did you use the stock cyl head bolts in the '81 Dasher, or did you install
some racing studs and nuts?

I have had early Rabbit diesels ('78 and '80) and thought they were waaaay
tooooo slow. Then when I purchased an '84 Rabbit Diesel it was almost as
fast as a gas Rabbit. Purchased in 1986 with 250K miles on it for only $2K
US from a dealership. They wanted it gone and I wanted it! WIN-WIN!
Well it was not really as fast as the gas Rabbits, but it was much better
than the '78 Rabbit Diesel in starting and acceleration.

There is a Quantum turbo diesel around me that is selling cheap. Floor is
rusted out and the engine now has a dead cylinder. I would need it to be
given to me so I can do something with the TD engine. The owners think that
it is still worth thousands. lol

I think I have seen one cracked block cause the oil and coolant to mix on an
early diesel. Usually I find that the cylinder head needs attention and of
course new head gasket and new bolts. ;-)
I vote for a bad gasket! I think I have seen that little oval shaped seal
become deformed on some of the head gaskets too.

later,
dave
(One out of many daves)


"Lost In Space/Woodchuck" > wrote in message
...
> BTDT. As far as headgasket thickness you are correct. But did I ever tell
> you about my 81 Hi-performance Dasher diesel? Among us techs it was a well
> know fact that the early diesel had problems starting in cold weather. I
> purchased a diesel for almost nothing because it needed a head due to
> warping. I fixed it by having a machine shop "true" the head on a CNC
> machine and installed a 1-notch headgasket vs the 2 or 3 it required. Also
> lowered the RPM limiter some. The result was an diesel that would run like
> a.... well hi-po diesel. It had so much compression it would cold start
> without pre-glowing the plugs. Ran it for 2 years then sold it to my
> friend who ran it into the ground.
>

"Lost In Space/Woodchuck" > wrote in message
...
> BTDT. As far as headgasket thickness you are correct. But did I ever tell
> you about my 81 Hi-performance Dasher diesel? Among us techs it was a well
> know fact that the early diesel had problems starting in cold weather. I
> purchased a diesel for almost nothing because it needed a head due to
> warping. I fixed it by having a machine shop "true" the head on a CNC
> machine and installed a 1-notch headgasket vs the 2 or 3 it required. Also
> lowered the RPM limiter some. The result was an diesel that would run like
> a.... well hi-po diesel. It had so much compression it would cold start
> without pre-glowing the plugs. Ran it for 2 years then sold it to my
> friend who ran it into the ground.
>
>
> "none2u" > wrote in message
> et...
>> You cannot use an oversized gasket on a VW diesel. The thickness is
>> selected based on piston height above the block surface to maintain valve
>> piston clearance and proper compression. Unfortunately This problem will
>> not be easy to find. He could be leaking anywhere, the head could be
>> cracked, or warped. the block bolt holes for the head could be cracked.
>> It could be anywhere. Even unrelated to the head change. He doesn't say
>> how much its leaking either. Or what shape the car is in. This could
>> help decide how to make a repair or find the leak.
>> "Lost In Space/Woodchuck" > wrote in message
>> ...
>>> did you clean out al the block head bolt holes? If not you may have
>>> cracked the block between the oil pressure feed and the head bolt near
>>> it. It was common on the early blocks to crack there even before the
>>> engine was taken apart.
>>>
>>>
>>> "JH" > wrote in message
>>> ups.com...
>>>>I replaced the cylinder head, cylinder head bolts, timing belt,
>>>> tensioner, and head gasket on my 78 VW Rabbit Diesel. It runs great,
>>>> but now leaks a small quantity of oil into the coolant. I then
>>>> replaced the head gasket (again), and applied the torque settings to
>>>> the bolts as outlined in the Bentley manual, but it still leaks.
>>>>
>>>> I did not have this problem prior to the head replacement. The
>>>> cylinder head is under warranty--my initial assumption is that there
>>>> is a problem with this rebuilt head.
>>>>
>>>> Could anyone help me out with some advice on how I should proceed?
>>>>
>>>> Thank you in advance!
>>>>
>>>> Jeff
>>>>That sounds very sweet, I love to hear diesel mods, that worked. high
>>>>compression performance dasher diesel. Youre just killing me!!
>>>>Unfortunately I was never into moding diesels, Just making them run
>>>>right ,forever. Although they are capable of taking it.
>>>
>>>
>>
>>
>
>

I think he said he changed the gasket twice already. I,m assuming its not
the gasket because of that. And he says it runs fine. I'm not assuming
anything else. It could be a cracked block bolt hole. Or a warped head. Or a
cracked head. That would be my next choice if I couldn't figure anything
without disassembly. I would like to know how much oil is leaking in the
antifreeze. And who rebuilt the head and to what standards.
"dave AKA vwdoc1" > wrote in message
...
> Did you use the stock cyl head bolts in the '81 Dasher, or did you install
> some racing studs and nuts?
>
> I have had early Rabbit diesels ('78 and '80) and thought they were waaaay
> tooooo slow. Then when I purchased an '84 Rabbit Diesel it was almost as
> fast as a gas Rabbit. Purchased in 1986 with 250K miles on it for only
> $2K US from a dealership. They wanted it gone and I wanted it! WIN-WIN!
> Well it was not really as fast as the gas Rabbits, but it was much better
> than the '78 Rabbit Diesel in starting and acceleration.
>
> There is a Quantum turbo diesel around me that is selling cheap. Floor is
> rusted out and the engine now has a dead cylinder. I would need it to be
> given to me so I can do something with the TD engine. The owners think
> that it is still worth thousands. lol
>
> I think I have seen one cracked block cause the oil and coolant to mix on
> an early diesel. Usually I find that the cylinder head needs attention
> and of course new head gasket and new bolts. ;-)
> I vote for a bad gasket! I think I have seen that little oval shaped seal
> become deformed on some of the head gaskets too.
>
> later,
> dave
> (One out of many daves)
>
>
> "Lost In Space/Woodchuck" > wrote in message
> ...
>> BTDT. As far as headgasket thickness you are correct. But did I ever tell
>> you about my 81 Hi-performance Dasher diesel? Among us techs it was a
>> well know fact that the early diesel had problems starting in cold
>> weather. I purchased a diesel for almost nothing because it needed a head
>> due to warping. I fixed it by having a machine shop "true" the head on a
>> CNC machine and installed a 1-notch headgasket vs the 2 or 3 it required.
>> Also lowered the RPM limiter some. The result was an diesel that would
>> run like a.... well hi-po diesel. It had so much compression it would
>> cold start without pre-glowing the plugs. Ran it for 2 years then sold it
>> to my friend who ran it into the ground.
>>
>

I am with you! Lets check out that rebuilt head!
But if the gasket is installed the same way twice and it was wrong or
incomplete. Could it even be the wrong gaskets? Like gaskets for the gas
engine maybe? Any sealing compound applied on the gasket?
I think someone mentioned that there is a small gasket/ring/seal that is
inserted inside of the head gasket to seal one the oil feeding the upper
cylinder head.
http://www.theautochannel.com/autopa..._63143tvi.html
I want to say that I have seen that oval shaped copper ring loose on some
diesel head gaskets, but it has been waaaay too long since I have taken a
diesel engine apart. Without that ring installed it may cause the problem
the OP is having. ;-)
If you note the application on this website it states that it fits the 75-84
Rabbit Diesel. AFAIK The engine changed in 1981 and so did the cyl head
gasket. So it is possible the gasket could be the wrong one.
Grasping at straws now! <g>

So the block needs to be throughly checked.
The head needs to be pressure tested or other means of checking for damage.

Now why was the original head taken off the first time? Same problem? Was
this "rebuilt" head properly serviced? And by whom? Can the original head
be serviced and reinstalled?
I would suspect this "rebuilt" head since he did not have this problem until
this head was installed.
So the only variables are a different head and a different gasket. I will
ASSuME that the installation was correct!

BTW I had a head gasket on my '91 Passat 16V that was allowing oil into my
cooling system. I have not seen this problem on any of the diesels yet. ;-)


"none2u" > wrote in message
...
>I think he said he changed the gasket twice already. I,m assuming its not
>the gasket because of that. And he says it runs fine. I'm not assuming
>anything else. It could be a cracked block bolt hole. Or a warped head. Or
>a cracked head. That would be my next choice if I couldn't figure anything
>without disassembly. I would like to know how much oil is leaking in the
>antifreeze. And who rebuilt the head and to what standards.

the only thing good was the price of a few $100. Other than that it was all
wrong. 4doors, beige outside and dark brown inside. But with 500psi of
compression it would run 4th gear to the limiter.


"none2u" > wrote in message
et...
>
> "Lost In Space/Woodchuck" > wrote in message
> ...
>> BTDT. As far as headgasket thickness you are correct. But did I ever tell
>> you about my 81 Hi-performance Dasher diesel? Among us techs it was a
>> well know fact that the early diesel had problems starting in cold
>> weather. I purchased a diesel for almost nothing because it needed a head
>> due to warping. I fixed it by having a machine shop "true" the head on a
>> CNC machine and installed a 1-notch headgasket vs the 2 or 3 it required.
>> Also lowered the RPM limiter some. The result was an diesel that would
>> run like a.... well hi-po diesel. It had so much compression it would
>> cold start without pre-glowing the plugs. Ran it for 2 years then sold it
>> to my friend who ran it into the ground.
>>
>>
>> "none2u" > wrote in message
>> et...
>>> You cannot use an oversized gasket on a VW diesel. The thickness is
>>> selected based on piston height above the block surface to maintain
>>> valve piston clearance and proper compression. Unfortunately This
>>> problem will not be easy to find. He could be leaking anywhere, the head
>>> could be cracked, or warped. the block bolt holes for the head could
>>> be cracked. It could be anywhere. Even unrelated to the head change. He
>>> doesn't say how much its leaking either. Or what shape the car is in.
>>> This could help decide how to make a repair or find the leak.
>>> "Lost In Space/Woodchuck" > wrote in message
>>> ...
>>>> did you clean out al the block head bolt holes? If not you may have
>>>> cracked the block between the oil pressure feed and the head bolt near
>>>> it. It was common on the early blocks to crack there even before the
>>>> engine was taken apart.
>>>>
>>>>
>>>> "JH" > wrote in message
>>>> ups.com...
>>>>>I replaced the cylinder head, cylinder head bolts, timing belt,
>>>>> tensioner, and head gasket on my 78 VW Rabbit Diesel. It runs great,
>>>>> but now leaks a small quantity of oil into the coolant. I then
>>>>> replaced the head gasket (again), and applied the torque settings to
>>>>> the bolts as outlined in the Bentley manual, but it still leaks.
>>>>>
>>>>> I did not have this problem prior to the head replacement. The
>>>>> cylinder head is under warranty--my initial assumption is that there
>>>>> is a problem with this rebuilt head.
>>>>>
>>>>> Could anyone help me out with some advice on how I should proceed?
>>>>>
>>>>> Thank you in advance!
>>>>>
>>>>> Jeff
>>>>>That sounds very sweet, I love to hear diesel mods, that worked. high
>>>>>compression performance dasher diesel. Youre just killing me!!
>>>>>Unfortunately I was never into moding diesels, Just making them run
>>>>>right ,forever. Although they are capable of taking it.
>>>>
>>>>
>>>
>>>
>>
>>
>
>