Stripped Cylinder Head

[nphilbro]

I was reassembling the cylinder head to the block on my 1977 85hp and one of the bolts wouldn't tighten - ugh! I pulled it out and the block thread was stripped.

I'm trying to find the right helicoil kit for it but I can't figure out what the bolt and thread size are.

The bolt is P/N 0307267

Any help?
Thanks

 

[will62]

Re: Stripped Cylinder Head

This link has more data than you would care to know about that bolt. Look it over, but I believe it is a 5/16" - 18.

http://www.parttarget.com/5306-00-1...67.html/-28B6ADBD-98F5-4281-BD9B-FE58510B1972

 

[sutor623]

Re: Stripped Cylinder Head

I was reassembling the cylinder head to the block on my 1977 85hp and one of the bolts wouldn't tighten - ugh! I pulled it out and the block thread was stripped.

I'm trying to find the right helicoil kit for it but I can't figure out what the bolt and thread size are.

The bolt is P/N 0307267

Any help?
Thanks

Just take your time when drilling/tapping. I put a helicoil in a stripped bolt hole and blew out the inside of the coolant jacket. ended up having the local welder fill it in with aluminum, grind the mating surface down smooth, drilled and tapped a new hole (original size) all for $40. Might wanna take a look into that direction, as that is just a tad more than the cost of a helicoil kit. The helicoils are hard to get right if you haven't done a ton of them. Another cool company is called Time-Sert. They are a nice route to go as well. Just my 2 cents and experience. If I ever strip out another head bolt I will use the local welder.

 

[boobie]

Re: Stripped Cylinder Head

I've used helicoils for yrs and nothing but. The trick is to take your time and be accurate in your drilling and tapping.

 

[F_R]

Re: Stripped Cylinder Head

Heli coils are the salvation of outboard mechanics. Couldn't live without them.

 

[nphilbro]

Re: Stripped Cylinder Head

A machinist friend of mine recommend them for my riding lawn mower a couple years ago but they didn't come 3/4" so I never tried it and gave the mower away.

Would a good hardware store be able to match it with the bolt?

 

[F_R]

Re: Stripped Cylinder Head

Take the bolt to that good hardware store, or an auto parts store such as Auto-Zone. If the ckerk knows which way is up, he will know what to sell you. If the first words out of his mouth are "What kind of car is it?", he doesn't know which way is up.

It might be cheaper to take the motor to the shop and have it done. It's only a 15 minute job.

 

[will62]

Re: Stripped Cylinder Head

Call your local shops and get a price on having it done. If you're not set up to do them yourself, you'll have to buy a kit with tap and insertion tool (~$30), and the kit will probably come with .469 length inserts. You need .938 for that bolt, and I don't think that you'll find that size at any local hardware store. Beyond all that, if you've never done one, I don't know if I'd want my first "experiment" to be in such a critical location... gearcase bolt - maybe, head bolt - not so much. If you're bent on pursuing it, call around for the 5CN938 inserts.

 

[archcycle]

Re: Stripped Cylinder Head

Hook up the trailer and take it down to a machine shop. It will really amaze you how quick and easy it is to just have someone else do it. You could buy the helicoil, buy the drill bits etc that you're probably going to burn through in the job, and take your sweet careful time. Or, you could just drag it to a shop and give them somewhere in the range of $35. When you get home with the finished product spend the hour or so you would have spent on the job skinning knuckles and cursing instead drinking a beer and congratulating yourself for your superior management and delegation skills.