Replacing head gasket any easy ways?

busakiller

Registered
I belive my head gasket is popped. Last time I rode the bike it got hot and then cooled down after I left the light and rode it a out 2 blocks to my house into the garage. Went to start it the other day and wouldn't idle. So I changed plugs. Pulled them out and they all looked the same. Except one was wet. But I had just tried to start it a couple minutes ago. I put new plugs in and the bike would pop and stuff but not start. So pulled plugs and checked them. One dry the rest were wet. So I checked for spark and all them light up fine. So I got the compression gauge out and started testing. 180 160 60 30. But the battery was pretty tired from trying to start it before. So I charged both batterys. As this bike has and 1397 motor and needs to batterys and 24 volt start. So both are charged and the bike turn's over and I get. 210 210 60 60. Do my 2 right cylinders are down and have the same psi. But it blows air out of both throttle bodies and sucks. So I am guessing the head gasket blew out in between the 2.

So I would like to know is there any ways to do this easy..... would like to be able to popen this off and put new gasket on and not have to retime the cams.
 
What is your experience of engine re-building? Of course the engine has to come out and be partially disassembled. Setting the timing is really not hard following the directions from the user manual.
 
They say you have to retime them if I remember correctly. Would I secure the hell out of them to the chain and try to put them back....Probably but I am a sort of whats the worst that could happen type of guy...

I'm still dealing with tons of little growing pains since building my 1397.
 
Greg. what growing pains ae left? With the manual FOLLOWING one step at a time, repeat one step at a time. Most can do it
 
Before you tear it down, perform a leak-down test to be absolutely certain where the compression loss is going. It may not be a head gasket, but most likely is. It pays to check and be certain.
The other thing is, get the cylinder head hardness tested and skimmed, and check/replace rings. With overheating rings can lose tension.
You also need to determine why it overheated in the first place. . .
thermostat faulty ? Radiator cap faulty ? water pump failure ? coolant leak? blocked or restricted flow in the radiator?
Just go through everything, it pays.
Keep us all in the loop, keen to know how it goes :thumbsup:
 
A buddy of mine came over and gave me a hand. Cylinder 1 had 280 psi cylinder 2 had 280 psi cylinder 3 had 60 psi and cyLinder 4 had 60 psi. We were pretty confused on that. We checked it twice. So we put the cylinder at td and put a little bit of air in them.1 and 2 cylinder would turn the motor over when we put air in it. So we did 3 and 4 and the air was coming out of the intake. So that's kinda weird that it's on those 2 cylinders. Looking for and place to bring the head to and have the valves checked and the head. The head gasket did look fine. And when turnine it over before I pulled it you could feel air coming out the intake.
 
When you pressurized the cylinders, are you 100% certain you tested each cylinder at TDC Compression stroke(firing)?
and your compression test showing 280psi in cyls 1 and 2 ??
Doesn't make sense to me.
Did you repeat the test a few times to eliminate the possibility of a false reading on the gauge?
Smells fishy . . . .
1536038740929.png
 
When you pressurized the cylinders, are you 100% certain you tested each cylinder at TDC Compression stroke(firing)?
and your compression test showing 280psi in cyls 1 and 2 ??
Doesn't make sense to me.
Did you repeat the test a few times to eliminate the possibility of a false reading on the gauge?
Smells fishy . . . .
View attachment 1584865
A horse walks into a bar...…. Bartender says "Why the long face" lol
 
I did a compression check 5 good time times. I used a screw driver and watched it go to the top and stop moving. I then put air in the cylinder and it was blowing out the intake. And moved the crank a couple of degrees back amd forth to see if it would stop and it would go from intake to exhaust.
 
I did a compression check 5 good time times. I used a screw driver and watched it go to the top and stop moving. I then put air in the cylinder and it was blowing out the intake. And moved the crank a couple of degrees back amd forth to see if it would stop and it would go from intake to exhaust.
Ok, sounds to me like you had the crank position at TDC 360deg away from the compression TDC position. (at the top of the exhaust stroke with the valves 'rocking')
So rotate the crank 360deg and recheck with pressure again for leakage
 
The head is off already..... taking the head in to have it checked. Before I did a compression check I took the air box off and I put my hands over the throttle bodies aND you could feel air blowing out. I will update this when I find the answer.
 
what a show gentlemen..... what a show...… kiwi is talking trigonometry and busakiller is using his fingers trying to add 2 and 2..... jk
Haha! I laughed out loud when I read your post and got some strange looks from the people in the docs waiting room lmao!
 
So today i found the problem. Well kinda. On cylinder 4 I found one intake valve leaking fuel. Not a lot but a little bit. Cylinder 3 didn't leak anything. I did check 3 and 4 cylinder exhaust valves to and nothing leaked. I did this test with no cam. So..... put the intake cam in and on cylinder 3 one intake valve was leaking like crazy. Cylinder 4 the one intake valve that was leaking before is leaking worse. So I popped the cam off and checked the shims and they look good. The buckets sit where they should as far I can see. So taking the head in to have the valves looked at and see if they find anything on how the valves are sticking open with the same shim that's been in the motor for the past year.
 
So today i found the problem. Well kinda. On cylinder 4 I found one intake valve leaking fuel. Not a lot but a little bit. Cylinder 3 didn't leak anything. I did check 3 and 4 cylinder exhaust valves to and nothing leaked. I did this test with no cam. So..... put the intake cam in and on cylinder 3 one intake valve was leaking like crazy. Cylinder 4 the one intake valve that was leaking before is leaking worse. So I popped the cam off and checked the shims and they look good. The buckets sit where they should as far I can see. So taking the head in to have the valves looked at and see if they find anything on how the valves are sticking open with the same shim that's been in the motor for the past year.
So what does that mean??
Did you actually get a feeler blade out and check to see what the shim to cam lobe clearance was???
If you had just done a leak down test BEFORE taking off the head, it may have just been a simple case of re-shimming the clearances on the leaking valves. Would have saved a lot of extra work and expense.
Anyway, so now the head is off, just send it away to have it ported and polished and a full valve job :thumbsup:
 
So what does that mean??
Did you actually get a feeler blade out and check to see what the shim to cam lobe clearance was???
If you had just done a leak down test BEFORE taking off the head, it may have just been a simple case of re-shimming the clearances on the leaking valves. Would have saved a lot of extra work and expense.
Anyway, so now the head is off, just send it away to have it ported and polished and a full valve job :thumbsup:
what is the square root of this forum to the third power?
 
So what does that mean??
Did you actually get a feeler blade out and check to see what the shim to cam lobe clearance was???
If you had just done a leak down test BEFORE taking off the head, it may have just been a simple case of re-shimming the clearances on the leaking valves. Would have saved a lot of extra work and expense.
Anyway, so now the head is off, just send it away to have it ported and polished and a full valve job :thumbsup:
what is the square root of this forum to the third power?


You guys don't work on your own bikes. And must not know anything about engines. Cause the valves should not get tight over time. I did a leak down test. I might of posted everything I did when trying to figure out what was wrong. From what it looks like that valve beat the seat up and caused the valve to get very tight.


I dropped the head off at ward performance and he's looking at it. He said the valves that are in my head are ones people stopped using cause they had this problem with them. I should know whats really wrong mid next week
 
Looks like my intake valves are made by kibble white. One of them mushroomed and beat the seat and was leaking. The other valve in cylinder 3 was mushroomed and was starting to beat the seat up. So getting all new intake valves so this problem doesn't happen. He said head looked great and the only problem was the shitty brand valves.
 
You guys don't work on your own bikes. And must not know anything about engines. Cause the valves should not get tight over time. I did a leak down test. I might of posted everything I did when trying to figure out what was wrong. From what it looks like that valve beat the seat up and caused the valve to get very tight.


I dropped the head off at ward performance and he's looking at it. He said the valves that are in my head are ones people stopped using cause they had this problem with them. I should know whats really wrong mid next week

Valves DO get tighter over time from the hardened seat being repeatedly pounded into the soft aluminum.
Hence the need for valve adjustment/shims.
 
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