Author Topic: how long after running a new head gasket to retorque  (Read 1351 times)

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Offline Redline it

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how long after running a new head gasket to retorque
« on: October 16, 2019, 12:40:26 PM »
by the way it seems head gaskets are in short supply here in the states. well i got 2 sets and both were faulty by erroded groves crossing the fire ring. those were sent back. crusinimage gaskets are 30 plus 10 for shipping, doesn't combine shipping for more either, 5 days from ordering in japan, it was here. so far it's working. haven't redlined it yet. after this last year i'm thinking of a different account name. maybe max halfthrottle.

one thing that i'm stumped over, is when adding the cylinders and head and cover, there's no preloading any thrust bearing, and as if it makes any difference because of the dowels if they get put in. but the way the cams where some are to the left and then some are to the right. so when buttoning them up. just go with if it looks fairly straight? or do you at least turn the crank over a few times to center cylinders, or the play in the crank will find and fill the play? oh and those 2 cam gear bolts a dot of lock time medium is recommended somewhere. i didn't add any only torquing them is kind of flimsy unless you use a gear wrench or like a clutch holder tool? i just held the kick starter with a knee and seemed to work.

Offline slikwilli420

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Re: how long after running a new head gasket to retorque
« Reply #1 on: October 16, 2019, 12:42:12 PM »
Head gaskets are plentiful and in many flavors from a variety of vendors. You can get copper, MLS or OEM style, price varies of course.
All you gotta do is do what you gotta do.

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Online RAFster122s

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Re: how long after running a new head gasket to retorque
« Reply #2 on: October 16, 2019, 01:11:30 PM »
If your cam gear is adjustable you better use Locktite and it is not a bad idea in general.  Another forum member did not and the bolts loosened and the gear shifted allowing a valve keeper to pop out when the valves hit the piston on that cylinder. Resulting damage, ruined one piston, destroyed combustion chamber and thus the head on a freshly rebuilt and ported stage 2.5 head work by MReich, very expensive oversight.
David- back in the desert SW!

Offline Redline it

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Re: how long after running a new head gasket to retorque
« Reply #3 on: October 16, 2019, 01:23:17 PM »
Head gaskets are plentiful and in many flavors from a variety of vendors. You can get copper, MLS or OEM style, price varies of course.

all i know is d silver spares and ebay, and plain stock gasket. if you know any vendors that i can deal with direct that have a web page or something, i'd appreciate that info. lately i'm getting stuff from people that seem to not have a clue of what their selling, or if they do it's that it's junk and they hope it'll go unnoticed.

Offline Redline it

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Re: how long after running a new head gasket to retorque
« Reply #4 on: October 16, 2019, 01:28:54 PM »
If your cam gear is adjustable you better use Locktite and it is not a bad idea in general.  Another forum member did not and the bolts loosened and the gear shifted allowing a valve keeper to pop out when the valves hit the piston on that cylinder. Resulting damage, ruined one piston, destroyed combustion chamber and thus the head on a freshly rebuilt and ported stage 2.5 head work by MReich, very expensive oversight.

i don't think it is adjustable, but so how long after a new head is running do you go over the head bolts or nuts again? i'll put a drop on the cam gear screws. maybe some medium strength.

Offline BenelliSEI

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Re: how long after running a new head gasket to retorque
« Reply #5 on: October 16, 2019, 01:29:25 PM »
I’ve heard Cometic makes a CB750 head gasket. Always used them on BMC “A” Series race engines, anyone tried them in their CB750? Good results?

Offline lash

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Re: how long after running a new head gasket to retorque
« Reply #6 on: October 16, 2019, 01:45:00 PM »
Cycle X has them in all flavors..
http://www.cyclexchange.net/Honda%20Page.htm
Analog mind in a digital world..

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Re: how long after running a new head gasket to retorque
« Reply #7 on: October 16, 2019, 03:18:08 PM »
South Sound Honda If OEM gaskets are still available is a good dealer source.
Cb750supply.com
Partsnmore.com
Partszilla.com
Vintagecb750.com
4into1.com
Z1enterprises.com
Cognitomoto.com
Dimecitycycles.com

A few parts sources in no particular order... ask if it is OEM or aftermarket and who makes it if it does not say...

Honda OEM gaskets are best in most situations.


David- back in the desert SW!

Offline low-side

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Re: how long after running a new head gasket to retorque
« Reply #8 on: October 16, 2019, 05:34:16 PM »
Coppergaskets.us can make gaskets to spec and is very reasonably priced.  I've ordered several custom head and base gaskets from Lani.

Offline Redline it

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Re: how long after running a new head gasket to retorque
« Reply #9 on: October 17, 2019, 01:37:10 PM »
thanks for all those replies, that'll work. i just emailed 58 dollars to japan for a top end gasket set from cruisinimage. i like the response time from them. last head gasket took 5 days. this order receipt came with warnings of possible delays with 3 zip codes, mine just happened to be one of them. we'll see. he packages them well also. i'd rather get US products for sure or factory honda if it's not too difficult to search for, or if it's 3 or 4 times the normal going rate. i'll let the showroom bikes get those.

Offline JoeDuc

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Re: how long after running a new head gasket to retorque
« Reply #10 on: October 22, 2019, 11:55:11 AM »
As Rainman said..."'Bout a hundred miles."

Offline Redline it

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Re: how long after running a new head gasket to retorque
« Reply #11 on: October 22, 2019, 03:39:50 PM »
As Rainman said..."'Bout a hundred miles."

thanks a lot. i spent about 2 or 3 days going over the nuts again and had only one which might of been a specialty nut, that cause 2 more around it to move some on the last day before running it. but the heat and cooling and compression has to have some affect in settling, so i'll try it again getting close to 100 miles. still no leaks yet, it's the first time in like 40 yrs that the fins aren't dripping.