My motor has / had a stripped out head bolt .. now need help checkiing head

[NRG]

Like I said above .. I have/had a stripped out head bolt on my 1979 Johnson 35hp, I found it checking torque on head bolts after replacing thermostat and gasket, So I thought about trying to fix with Helicoil without removing head .. decided that was a bad idea .. so I jerked the head , all the bolts but 2 where way over torqued barely got a couple of them off.

Any way when I but a straight edge on the head in any direction the round piston areas are 6-7 thousands all the other surfaces are within .003 tolerances , the middle cylinder areas all appear to be 6-7 no matter where on them I check .

Any way I can take off this 3-4 thousands without have machined ? or does anyone here do head machining work .. what would the cost be ?

Attached is pic of the low spots, the middle is the lowest at about 6-7 thousandths and tapers to 1 or less at the bolting edges

Any help greatly appreciated

 

[Guest]

You might try laying it on a wide belt sander for just a bit, use a fine belt. Put the belt sander in a vise to hold it upside down.

 

[Bubbakat]

RE: My motor has / had a stripped out head bolt .. now need help checking head

You will need a good flat surface and lay you a sheet of 80 to 120 grit paper on it and take that head and work it in a circular motion until it is even all the way across. When replacing that gasket ask for the gasket with the shinny surface so you won't have to worry about putting a sealer on it. I have done many a head cover like this and it does work. Back in my younger days all the old tech had to do it this way, couldn't afford to have it milled down.
I use a thick piece of tempered glass for my flat surface to work on.

When replacing the threads in the block I have found that the steel threaded inserts work the best instead of the helicoils. Just add some locktite to the insert and screw it into the hole and let dry.

 

[NRG]

RE: My motor has / had a stripped out head bolt .. now need help checking head

Bubbakat - 2/24/2008 6:09 AM

You will need a good flat surface and lay you a sheet of 80 to 120 grit paper on it and take that head and work it in a circular motion until it is even all the way across. When replacing that gasket ask for the gasket with the shinny surface so you won't have to worry about putting a sealer on it. I have done many a head cover like this and it does work. Back in my younger days all the old tech had to do it this way, couldn't afford to have it milled down.
I use a thick piece of tempered glass for my flat surface to work on.

When replacing the threads in the block I have found that the steel threaded inserts work the best instead of the helicoils. Just add some locktite to the insert and screw it into the hole and let dry.

I looked online .. at advanced, autozone, and napa they only have helicoil , I did find some time-sert ones but the kit is very pricey 65.00 for the kit on ebay

What brand did you have in mind ? all I can find other than that one are all like the helicoil brand , I can take the head to work , we have a good sized machine shop there .. It just would take a while for one of them to have time to work it in.. I may try the sanding first to see what I can do with it

 

[Bubbakat]

Post the thread size and bolt size of it and I may just have a steel insert im my stash.


If you have a way to bring it down to lvel without the sand paper deal then go for it, but beware it won't take much to bring it down to far. You sure don't want any heat build up while shaveing it down.

 

[digitalcb]

"I use a thick piece of tempered glass for my flat surface to work on. "

Bathroom scales are a good source for glass.

When they die pry the feet/load cells off and you have a great piece of tempered glass.

 

[NRG]

digitalcb - 2/24/2008 11:46 AM

"I use a thick piece of tempered glass for my flat surface to work on. "

Bathroom scales are a good source for glass.

When they die pry the feet/load cells off and you have a great piece of tempered glass.

Glass to lay the head on with sandpaper on it ? picture preferable when explaining to the learning handicapped lol

 

[Bubbakat]

Lay the glass on a table top and lay sandpaper on it and work the head with even amount of pressure and in a circular motion.

 

[NRG]

Well I gotta a head that has been machined flat, and media blasted to remove carbon, old paint, and other junk, now if I just had a new head gasket lol .. nobody in town had one in stock emoDoh that I could find anyway.. oh well .. I ordered off the net since Id have to order it from any other dealer in town .. so I just ordered my self cheaper anyway

50 bucks for new head gasket, new plugs, new thermostat cover gasket, and new deflectors.. included shipping any way .. in a few days my parts will be here and I can put my motor back together .. and back to fishin
I got the stripped threads fixed on the block too today.

This motor should be rock solid now .. rebuilt carb, new tale tale elbow in motor ( connects water line to block ), new water hose, cleaned out stopped up tale tale hole in bottom motor housing, new thermostat, new gas lines, new oil return lines, rebuilt fuel pump, new impeller, and head machined. and tapped all the bolt and screw holes.

I sure hope this is all for a while lol

Id hate to think what this would have cost me at a service shop at 75 per hour

 

[Bubbakat]

Nothing like doing the job right. As for what it cost at a shop, would be hard to put a price on it and it most likely would have been hard to find a shop that would have taken the time to do it.

 

[dustman]

If you ever run into this again. I can do anything but port work on a outboard. My father builds fuel motors and top alcohol drag motors. I can use his shop anytime to help someone out in need. Like the head, I can put in on the head surfacer, make about 3 good swipes with the rock and it would be done. I was just going to let you know just incase something ever happens. thanks