http://cgi.ebay.co.uk/BMW-530-730-M...arts_Vehicles_CarParts_SM&hash=item45f529e1cd
It seems to have more holes on the water side of the head?
Thanks,
Rohan
It seems to have more holes on the water side of the head?
Thanks,
Rohan
Will this head gasket be ok for my stock 3.0 engine?
- Thread starter 30csl
- Start date
Head gasket
The one in the ebay ad is for a late m30. (88-up) Yes, it has extra coolant passages which is not good.
Usually, the combos are for the head gasket from 87 down. ( discounting the early 3.5, M90 Euro which uses the euro gasket only).
But you didn't say what you're combo is- early block later head?
I would pass on this gasket and look for the earlier version.
The one in the ebay ad is for a late m30. (88-up) Yes, it has extra coolant passages which is not good.
Usually, the combos are for the head gasket from 87 down. ( discounting the early 3.5, M90 Euro which uses the euro gasket only).
But you didn't say what you're combo is- early block later head?
I would pass on this gasket and look for the earlier version.
84E24
Well-Known Member
Head gasket
I have a Gasket Set for my 1973 3.0cs and i also have a question about the head gasket.
On realoem and penskeparts they list 2 head gaskets.
1) 11 12 9 065 638 that is 1,8 mm or .0708"
2) 11 12 9 065 639 that is 2,1 mm or .0827"
The orginal gasket that came off the engine was the .0708" but the gasket in the complete kit is the .0827". Will that make a difference ?
Last week I took my orginal head off to fresh'en up and new seals.... Found out that it had cracks in #2, #3 and #5.
Metric just shipped me a HiFlo ST Sport 6 Cylinder Head and should be here by Thursday. I hope to have it installed and running with my triple DCOE 40's before The Vintage.
Looks like I won't need the complete Gasket Kit if anyone is interested .....
Steve
I have a Gasket Set for my 1973 3.0cs and i also have a question about the head gasket.
On realoem and penskeparts they list 2 head gaskets.
1) 11 12 9 065 638 that is 1,8 mm or .0708"
2) 11 12 9 065 639 that is 2,1 mm or .0827"
The orginal gasket that came off the engine was the .0708" but the gasket in the complete kit is the .0827". Will that make a difference ?
Last week I took my orginal head off to fresh'en up and new seals.... Found out that it had cracks in #2, #3 and #5.
Metric just shipped me a HiFlo ST Sport 6 Cylinder Head and should be here by Thursday. I hope to have it installed and running with my triple DCOE 40's before The Vintage.
Looks like I won't need the complete Gasket Kit if anyone is interested .....
Steve
MMercury
Well-Known Member
- Messages
- 481
- Reaction score
- 5
All things being equal, a thicker gasket will result in slightly reduced compression.
As you are probably aware, when aluminum heads are removed (for any number of reasons) they often require machining or planing, wherein some of the mating surface is removed. At some point, too much surface material can be removed. Thicker head gaskets accommodate this situation.
The factory provided minimum head thickness recommendations (See below). Folks often ignore these recommendations to gain compression. The down side to this equation is retarded valve timing - absent cam gear modification/s.
With any replacement head that isn't new, it is always prudent to measure its thickness to see if its within factory specs. Given your direct relationship with MM, I would consider asking for their gasket recommendation/s.
hth.
"When flat facing the cylinder head mating surface, the total thickness of the cylinder head in its standard from A = 129.0 ± 0.1 mm (5.0787 ± 0.0039 in) must not be reduced by more than 0.5 mm (0.0197 in)."
11 12 621
As you are probably aware, when aluminum heads are removed (for any number of reasons) they often require machining or planing, wherein some of the mating surface is removed. At some point, too much surface material can be removed. Thicker head gaskets accommodate this situation.
The factory provided minimum head thickness recommendations (See below). Folks often ignore these recommendations to gain compression. The down side to this equation is retarded valve timing - absent cam gear modification/s.
With any replacement head that isn't new, it is always prudent to measure its thickness to see if its within factory specs. Given your direct relationship with MM, I would consider asking for their gasket recommendation/s.
hth.
"When flat facing the cylinder head mating surface, the total thickness of the cylinder head in its standard from A = 129.0 ± 0.1 mm (5.0787 ± 0.0039 in) must not be reduced by more than 0.5 mm (0.0197 in)."
11 12 621
head, gaskets, milled... muddy waters
The consideration of the thickness also corresponds to the sealing of the timing cover.
If the head is cut, but not the upper timing cover there is a chance that the gaskets and the sealing surfaces will be off by the corresponding cut.
Hence the thicker gasket. Not withstanding a zero deck/ piston clearance for performance.... I assume if you did that you better darn well know what you're doing.
Usually, when the head is machined so too is the upper timing cover.
Using the thicker gasket on a new or uncut head would have the opposite effect- not enough clearance for clamping.
In the end, most people never realize the difference. The thicker gasket is rarely used. ( I think MM uses new AMC heads)
I've always found that the judicial use of RTV on the top of the lower timing case to upper timing case ( especially the corners) works to seal the most stubborn and typical of M30 front leaks.
The consideration of the thickness also corresponds to the sealing of the timing cover.
If the head is cut, but not the upper timing cover there is a chance that the gaskets and the sealing surfaces will be off by the corresponding cut.
Hence the thicker gasket. Not withstanding a zero deck/ piston clearance for performance.... I assume if you did that you better darn well know what you're doing.
Usually, when the head is machined so too is the upper timing cover.
Using the thicker gasket on a new or uncut head would have the opposite effect- not enough clearance for clamping.
In the end, most people never realize the difference. The thicker gasket is rarely used. ( I think MM uses new AMC heads)
I've always found that the judicial use of RTV on the top of the lower timing case to upper timing case ( especially the corners) works to seal the most stubborn and typical of M30 front leaks.
m_thompson
Well-Known Member
The PO of my Coupe did this and broke the distributor drive parts on the front of the camshaft because the upper timing cover was misaligned relative to the cylinder head.
Thanks for the advice and help guys. I will go ahead and get the head checked and then decide upon a gasket as i might need a thicker one.
Would the later gasket with more holes for the waterways not be a good thing to imprive circulation though?
Regards,
Rohan
Would the later gasket with more holes for the waterways not be a good thing to imprive circulation though?
Regards,
Rohan