Kubota D950- do the exhaust studs go into the water jacket ?

[WNCHillbilly]

Dealing with a Kubota F2100 4x4 tractor/mower. It has a D950 engine that runs well, but I just got it. The exhaust system has been off at some point and there are two studs that mount the muffler/exhaust that go into the head. When one fills the radiator engine full of water/antifreeze mix- the mix leaks out two of the studs in the head that are missing. There is no, none, zero in terms of water getting into the oil. The engine has good power. However when you put coolant into the engine- water comes leaking out of the two exhaust manifold stud holes.

Do the exhaust studs(the studs that the exhaust manifold bolt to) enter the water jacket ? Only two studs are missing and those two studs are where I have a water leak.

Can anyone tell me the correct stud thread and pitch for this exhaust stud ?

PS: No water in oil. No oil in water. Thanks !

Any help is greatly appreciated. Thanks very much.

 

[GreensvilleJay]

Well this is very frustrating.. went to K-partsonline, F2100, look at both head and exhaust drawings. Studs are shown, NO part numbers !!! grrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr.
It does look like 3 long ones, 3 shorter ones.
so, can you carefully remove one 'lower' and one 'upper' stud ?
Maybe Google can find them "D950 exhaust studs" ??

ok..."kubota D950 exhaust studs" finds this as 1st hit...
https://www.orangetractortalks.com/...ze-pitch-for-kubota-d950-exhaust-studs.29750/ !!
has part number, seems all 6 studs are the same .

Kubota #15381-91532 STUD

STUD

www.messicks.com

shows a picture...gee 1" long ?? don't think they're the correct ones.....

maybe Google has to wait for Mr. Sun to come up ?

 

[woodman55]

A bit unrelated, but on some of the older small perkins, a few of the studs went into the water jacket. We just put pipe dope on them when we installed them, always seemed to work.

 

[GeoHorn]

A bit unrelated, but on some of the older small perkins, a few of the studs went into the water jacket. We just put pipe dope on them when we installed them, always seemed to work.

Same with head bolts on the N-Fords…. Pipe dope…..or Permatex No. 2.

 

[D2Cat]

Yes, those studs go into the water jacket. I can't remember which one. Might contact North Idaho Wolfman, he can give you the details.

 

[WNCHillbilly]

Kubota stands by their story the stud is only 1" long. That is not possible. I realized that I have a D750 head with exhaust studs, and Messicks lists it as an engine that uses the same stud. There is more than 1" protruding from the head. I mic'd it and then read it and it was a little over 1.25".

It appears though the two "problem children" studs definitely go into the water jacket(one of the spare D750 heads is bare except for a few of the studs. I did a sort of "flow test" and confirmed on both spare heads that water does flow where those two studs are and the two studs have to be sealed with teflon. If I had a size I might be able to find them locally.

The local kubota parts guy: "Who the h#ll is still using a 1992 F2100 ?"
Me: "Me"
Local kubota parts guy shakes head.

 

[woodman55]

Kubota stands by their story the stud is only 1" long. That is not possible. I realized that I have a D750 head with exhaust studs, and Messicks lists it as an engine that uses the same stud. There is more than 1" protruding from the head. I mic'd it and then read it and it was a little over 1.25".

It appears though the two "problem children" studs definitely go into the water jacket(one of the spare D750 heads is bare except for a few of the studs. I did a sort of "flow test" and confirmed on both spare heads that water does flow where those two studs are and the two studs have to be sealed with teflon. If I had a size I might be able to find them locally.

The local kubota parts guy: "Who the h#ll is still using a 1992 F2100 ?"
Me: "Me"
Local kubota parts guy shakes head.

Thread pitch will also be a factor, and may be harder to gauge. They will be metric for sure, and most likely 8 or 10 mm, could be 6mm, or maybe even 12, but I doubt it.

 

[ChipJr]

Look Under Intake Manifold in parts.

 

[woodman55]

 

[woodman55]

View attachment 86081 View attachment 86081

No code has to be inserted here.

No code has to be inserted here.

I am thinking #90 is what you are after.

 

[GreensvilleJay]

Not #90. heck, they're NOT even on the drawings !, qty 6 required, to secure the exhaust manifold to the head.
3 big holes with 2 holes each on diagonals,on the side of the head.
I looked at that drawing, plus the 'muffler' one...
I'd have thought those studs and washers WOULD have been shown as they're kinda important.
Maybe another machine, uses same engine, will have them shown ???

 

[ChipJr]

Like I said above, I looked and it shows 3 studs one number and 3 another,
but under INLET manifold, not intake, sorry.
.

 

[woodman55]

No code has to be inserted here.

Not #90. heck, they're NOT even on the drawings !, qty 6 required, to secure the exhaust manifold to the head.
3 big holes with 2 holes each on diagonals,on the side of the head.
I looked at that drawing, plus the 'muffler' one...
I'd have thought those studs and washers WOULD have been shown as they're kinda important.
Maybe another machine, uses same engine, will have them shown ???

No code has to be inserted here.

On the intake page these are the two studs listed for the exhaust. #90 is $5.52

 

[woodman55]

No code has to be inserted here.


No code has to be inserted here.

On the intake page these are the two studs listed for the exhaust. #90 is $5.52

 

[woodman55]

I am not very good at copy/paste, so I made a bit of a mess. Hope this mess helps.
#90 is 1569491490 #80 is 1569491480

 

[GreensvilleJay]

re:

On the intake page these are the two studs listed for the exhaust. #90 is $5.52

well ain't that just great... EXHAUST studs in the INTAKE page....sigh
I'm betting #80 is shorter then #90 ?

 

[woodman55]

re:

On the intake page these are the two studs listed for the exhaust. #90 is $5.52

well ain't that just great... EXHAUST studs in the INTAKE page....sigh
I'm betting #80 is shorter then #90 ?

One was about $28 and the other $5ish.

 

[GreensvilleJay]

YIKES !!! my luck, I'd need the $28 ones.....

 

[woodman55]

YIKES !!! my luck, I'd need the $28 ones.....

28 canadian