the exhaust port is missing a piece

[svo58]

I just got a 84 honda 70 ATC .Were the header pipe bolts to the engine a piece was broken off .What can i use to build it up after i bolt the exhaust on that will stand the heat,is there anything for this .Will JB weld work on that much heat.The piece is broke on the engine,what's my allturnatives with out replaceing the head,thanks ............svo58

[nicholas]

Im brand new to this forum, but I'm hooked on my little 70. I am restoring my 85' and I have the same problem. There is a chip out of the head where the pipe comes in. I think Im just going to replace the head. It functions fine but it bothers me the way it looks. Can I just bolt a new head on or do I need to replace the piston, etc. Im also needing tips/pics of how to paint my exhaust. Its in fairly good shape, but is rusty. Ive never had any luck painting mufflers and I dont think I want to replace it with a cobra exhaust. Anyone have any suggestions

[atctim]

Hey guys - I know what you are talking about - all 70's are like that - it is not actually broken - just looks that way - it is the way they are made.

Post up a picture to make 100% sure - but I know what you are talking about - looks really strange.

[RedRider_AK]

I know exactly what you guys mean. I think the problem stems from that area being very hot from operation, and then some guy riding the machine goes through water and it cracks off. Then you can't bolt your exhaust on all the way... :(

I don't think JB Weld will work, sorry, it's just not that strong.

[thefox]

Welcome to the board Nicholas.

Like Tim said there is what looks to be a missing piece in the stock exhaust flange. Here are 2 pictures of my 70 head showing how it is supposed to look. It is possible that you have another piece broken though; I have seen that happen when people try to get out very rusted exhausts.

If you do need to replace the head you don't have to remove the cylinder or piston but since you are in there I would pull the cylinder to check it out then re-ring the piston and hone the cylinder.

For the exhaust sandblasting is the only way to go. Then paint it with a good high-temp paint.


Again, these pictures show the normal, factory missing piece.

[nicholas]

You guys are great. Thanks for the help. Ill post some pics of my 85' atc 70 soon.