As a temp repair I would use RTV until I had the new gasket. You could cut down the old one if it is still in reasonable condition & stick it all back together with RTV. There are those on here that will tell you not to & you should wait till the new gasket arrives, but when you are up to your neck in it, sometimes you need to work outside the square.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving