TRX250R.ORG

Workshop => Engine and Bottom End => Topic started by: 87cclR on July 09, 2015, 08:42:49 PM

Title: Head Gasket Concerns
Post by: 87cclR on July 09, 2015, 08:42:49 PM

Putting the engine back together - the head gasket that came out of it is a 3 piece with metal center (1987 TRX250R). The gasket in the Cometic top-end kit I bought is a single piece, pretty thin :\
1. Can the original head gasket simply be reused if it's in good shape?
2. What's the deal with the 3 piece gasket vs the thinner aftermarket one?
Advice/experience/comments welcomed.....

Title: Head Gasket Concerns
Post by: Jerry Hall on July 09, 2015, 10:11:37 PM

Some guys have success with the single thickness metal gaskets but the single thickness gaskets are really for cylinders that do not have a sleeve and may leak when the cylinder is at operating temperature and wide open throttle.

Title: Head Gasket Concerns
Post by: Tbone07 on July 10, 2015, 08:24:53 AM

Quote from: 87cclR;55953

Putting the engine back together - the head gasket that came out of it is a 3 piece with metal center (1987 TRX250R). The gasket in the Cometic top-end kit I bought is a single piece, pretty thin :\
1. Can the original head gasket simply be reused if it's in good shape?
2. What's the deal with the 3 piece gasket vs the thinner aftermarket one?
Advice/experience/comments welcomed.....

In my opinion.....everybody should go out and have their heads cut for o-rings.

I've used the thin piece of the 3-part head gasket before and it leaked a good amount. Never used the Cometic single piece

Title: Head Gasket Concerns
Post by: 87cclR on July 10, 2015, 11:18:56 AM

Thanks for the info/advice. Heading to eBay to order an OEM gasket based on the Honda part number. As far as having the head machined for an o-ring, is there a vendor or service shop you can recommend for this?

Title: Head Gasket Concerns
Post by: rk88r on July 10, 2015, 08:04:18 PM

You can order an 87ish cr 250 head gasket. They are sandwich style and a little thinner than the trx one.

Title: Head Gasket Concerns
Post by: 87cclR on July 10, 2015, 08:34:16 PM

Ordered a NOS 12254-HB9-013 gasket, this is what was called out by the parts fiche provided by Service Honda for an 87 250R. Hoping it's the correct one, my communications with the seller lead me to believe as such, come Monday I'll know. Thanks for all the assistance, will update when it arrives.

Title: Head Gasket Concerns
Post by: Jerry Hall on July 14, 2015, 05:12:52 PM

Multi-layer head gasket 12254-HB9-013  fits the 87 4 Trax and is around .055" thick.  I usually use the multi-layer head gasket 12254-KS7-881 that fits the 85 ATC 250 R as well as many of the CR250 in the mid to late 1980s and is about .040" thick.

Title: Head Gasket Concerns
Post by: 87cclR on July 14, 2015, 07:15:41 PM

Quote from: Jerry Hall;56041

Multi-layer head gasket 12254-HB9-013  fits the 87 4 Trax and is around .055" thick.  I usually use the multi-layer head gasket 12254-KS7-881 that fits the 85 ATC 250 R as well as many of the CR250 in the mid to late 1980s and is about .040" thick.

Thanks for the info. I installed the HB9, and it was .055 thick, I verified the measurement. Hopefully it makes decent compression.