1993 940 oversize head gasket

Post by **bskeels** » 09 Sep 2015, 11:13

Does anyone make a .020 over head gasket for the B230FT? I haven't been able to locate one looking on most of the gasket manufacturer's sites (Victor Reinz, Fel-Pro, etc.) Can anyone help or can I use the head as is, had it machined .020. Thanka

Post by **precopster** » 09 Sep 2015, 11:39

With .020 larger bores if the cylinder bores had been machined .020 larger then you would still use the standard head gasket.

I machined a Mitsubishi engine's bores to 0.030 and still used the standard head gasket for over 80,000kms before car was sold with no issues.

If you've machined a cylinder head 0.020 then you effectively have a SMALLER combustion chamber due to the eliptical shape being slightly reduced so I am rather confused by your post.

93Regina · Post by **93Regina** » 09 Sep 2015, 11:39

bskeels wrote:Does anyone make a .020 over head gasket for the B230FT?

Might ask here, or here.

Post by **JDS60R** » 09 Sep 2015, 12:53

The head has area in it that show how low you can skim the head to make it level. As long as the head was cut above spec you are fine. 20 thou is a major cut. Normal is about 6 thou.

I'll try to find a pic of the cut markers.

Post by **JDS60R** » 09 Sep 2015, 13:08

Nothing on it here at work. Most of my 240 stuff is at home. I'll try to find it and post it if I do.

I thought I remembered a detent next to a port or a square block off to one end. Not sure. I will check - hopefully someone chimes in with the correct answer.

Your machinist should know for sure. You may want to ask him.

Post by **JDS60R** » 09 Sep 2015, 13:11

It might be that detent on the top cooling port between the two cylinders on the right.

93Regina · Post by **93Regina** » 09 Sep 2015, 15:20

bskeels wrote:Does anyone make a .020 over head gasket for the B230FT?

Over at T-brick forum, John V, outside agitator , should know. That URL cited only works when logged into forum.

Post by **bskeels** » 09 Sep 2015, 23:32

just to clarify a little better, the head has been machined to .020, shop originally measured at .017 out, which according to Haynes and Alldata is acceptable, I had it machined to the max of 0.020 according to those specs. I searched Volvo dealers websites and a few gasket manufacturers and haven't found a oversized head gasket. I guess the next question is do I need one or is a standard one fine?

difflock54 · Post by **difflock54** » 10 Sep 2015, 20:43

Would it not be a critical issue if the motor is an interference type which some 940's are fitted with ?
Otherwise , as precopster stated above you would merely have a lessor volume in the combustion chambers but no risk of the valves contacting the top of the pistons.

see this link. http://www.aa1car.com/library/timing_be ... ngines.htm
list below is pasted from the link.

VOLVO

1993-98 2.3L 5-cylinder C70 S70 V70 850

1993-98 2.4L 5-cylinder 850 V70

1991-93 2.3L 5-cylinder 940 (Canadian)

1986-94 2.3L 4-cylinder 240 740 760 780 940

93Regina · Post by **93Regina** » 10 Sep 2015, 22:05

difflock54 wrote:Would it not be a critical issue if the motor is an interference type...

Volvo has specs to how far down head can go; stay within that spec, everything is OK.

Once exceeded, if timing belt slips, the valves will kiss the pistons.

However, I don't know when valves will hit pistons when Head is shaved too much.

I've got a B230F engine overhaul book, but I think the spec can be found elsewhere.