Super Jet B-Pipe Getting Way to Hot

[imabadfish]

I have a 91 superjet with a 701 / 61x and I have read a bunch of threads about why my pipe would be getting so hot.

I was able to blow through all the lines easily so it doesn't seem clogged.

I never had an issue until I put a Pro-tech head on. I torqued the head down following the manufacture's instructions and even checked after about 25 minutes to make sure the bolts were still torqued down enough.

The only difference in the setup of the cooling lines is that the stock head was tapped on the top of the head and not the side. (In the picture on the left side)

Something I did try:

It didn't look like there was enough water flowing from the left side of the head to the top of the b-pipe so I capped the line coming from the right side of the head and more water made it to the end of the pipe (stinger) but it still got way to hot.

Any ideas what's going on? Here's a pic of my setup. Trying to get a few more rides in before it gets to cold. any help would be appreciated! Thanks

 

[imabadfish]

Oh, i also had a flow control valve on the line close to the stinger but with the heat the line pretty much melted away around the valve so i just removed it for now.

 

[sjetrider]

sounds like your adjuster screws are clogged. Is the entire motor and exhaust mnfld to ho or just the pipe? Take out your top water adjuster screw in the headpipe and run a tiny (.032") drill bit down in it turning it with only your fingers and then blow it out.
Your sure no lines are loose at the pump or to the manifold?
Is that an O-ring head and is it on correctly, they will bolt on backwards.

 

[imabadfish]

It seems to be just the pipe. getting the sizzle. The motor is hot but i figured it would be warmer anyway with the higher compression. Running 37cc domes in the head.

I know all the lines are tight I just replaced most of them and replaced my bilge pump like 3 weeks ago. I'll check again. I used brand new o-rings on the head and from my understanding it only bolts on one way because the pro-tec head is only girdled on one side. The girdle bolts would be way to long for the exhaust manifold side.

I'll check the top water adjuster screw. I didn't want to mess with it because i heard they can just crumble away when you try to adjust them. and i'm not really sure how to tune all 3 screws in on the pipe anyway...

Thanks for the help.

 

[sjetrider]

I generally close all but the top screw and start with it out 1 full turn and check the pipe, you want it hot but not sizzling hot. Usually if its just the pipe your problem is that those holes under the adjuster screws are loaded, clogged with crap.
A trick when removing them is to loosen the nut then double the nut up and use the allen wrench and the nuts at the same to back the bolt out so not to strip the allen head (that is usually the issue). Start with only the top one and clean out the little hole under the adjuster then run it 2 turns out and see how it works. wORK IT IN FROM THERE till the chamber sizzles after a few minutes of HARD riding, then back it out a quarter turn or so. Also check your flow contro valve with a pop off GA or my just leaving it disconnected and see how much water is getting to the stinger and when.

My concern first is that your not getting enough water period as you said the flow control line nearly melted?????

 

[oxnard111]

I generally close all but the top screw and start with it out 1 full turn and check the pipe, you want it hot but not sizzling hot. Usually if its just the pipe your problem is that those holes under the adjuster screws are loaded, clogged with crap.
A trick when removing them is to loosen the nut then double the nut up and use the allen wrench and the nuts at the same to back the bolt out so not to strip the allen head (that is usually the issue). Start with only the top one and clean out the little hole under the adjuster then run it 2 turns out and see how it works. wORK IT IN FROM THERE till the chamber sizzles after a few minutes of HARD riding, then back it out a quarter turn or so. Also check your flow contro valve with a pop off GA or my just leaving it disconnected and see how much water is getting to the stinger and when.

My concern first is that your not getting enough water period as you said the flow control line nearly melted?????

Great tip, I wouldn't have thought of that.

 

[imabadfish]

cool thanks for the help. I'm at work at the second you know what size nut that is to pull that trick off?

 

[djkorn1]

Could be a leaky o ring or head gasket. That will stop water flow immediately.

 

[sjetrider]

its 3/8 wrench size, standard really, Just take one off the middle adjuster and use it, the nuts come off easy, its the adjuster bolts that seize up.

If it is an O-ring or head gasket your pissers will sputter when running, blowing a little exhaust out of them and they will not have a consistant stream, easy to tell cracked domes and blown head O-rings like that. Exhaust will be in your water stream.

 

[Nuklear6]

One thing I think your forgetting to tell us is what part of the pipe is too hot? Is it just the chamber or is it the head pipe hot as well. Def need to take whatever water screw you have open (on the head pipe) completely out and insure that a 1/16th drill bit will pass through the hole into the exhaust passage (not just into the water jacket).

If all of this is clear I would bet on it being a head gasket/o ring problem as said above

 

[imabadfish]

its 3/8 wrench size, standard really, Just take one off the middle adjuster and use it, the nuts come off easy, its the adjuster bolts that seize up.

If it is an O-ring or head gasket your pissers will sputter when running, blowing a little exhaust out of them and they will not have a consistant stream, easy to tell cracked domes and blown head O-rings like that. Exhaust will be in your water stream.

This sounds more like what is happening, but I put brand new o-rings and new domes in though. I put a little grease on the o-rings to keep them in place when I put it on as well. Pulling the head when I get home.

 

[tor*p*do]

are you running dual cooling?
if not, you are sending too much water overboard with the front of the head pisser
put a restrictor in the line from the front of the head to push more water through the pipe

 

[imabadfish]

are you running dual cooling?
if not, you are sending too much water overboard with the front of the head pisser
put a restrictor in the line from the front of the head to push more water through the pipe

no its not dual cooling although it probably should be since the water down here gets like 90 degrees in the middle of the summer. I actually capped that line your are talking about and it pushed more water through the pipe but the chamber still got hot. It also made the ski run like crap it had no bottom end and felt like it was only running on one cylinder.

I'm gonna put my stock head back on and see how it does.

 

[Big Kahuna]

pull the line coming off the head that goes to the pipe, do this with the ski in the water, crank the ski and ride it with the hood off, how much flow are you getting?

 

[Dustin Mustangs]

Are you sure the domes are 37cc? Have you checked your cranking compression??

 

[imabadfish]

Ordered the domes from pro-tec brand new and they said 37 on them. Going to go pull the head right now.

 

[imabadfish]

sorry if the pics are a little blurry I don't have a camera at the moment. sooo...

I pulled the head off and I saw some spots on the o-rings that looked pinched near the bolts. Then I saw this:

It's broken.

I'm a little upset considering I bought a new o-ring kit from pro-tec. I have the old ones that were in it when I bought the head I am going to try and put those back in there.
Here's pic of the head with the domes in it (they are 37cc) looks almost new...


So something else I noticed though... Excuse my complete lack of engine knowledge on this but the spark plugs don't seem to be the right size anymore. Was I supposed to change the size (gap) spark plugs I use when I changed out the head? On the 37cc domes it looks like the spark plug needs to screw in about 5-6 more threads but on the stock its level with the inside of the dome. pics... pro-tec on the left - stock on the right...


If I need different plugs how do I figure out what size I need?

Thanks again for the help guys.

 

[Big Kahuna]

BR8ES plugs with Aftermarket heads. OEM uses BR8HS (Half Shaft).

you can superglue the oring back together.

 

[sjetrider]

BK is correct, the ski will run like crap with BR8HS in there due to lower compresion and spark location to the piston, Advanced has the HARD TOP BR8ES plugs for like $2 ea.. WOW, you had to be super pissed when you bolted this new head on and went to the lake. Use a little 3bond at end of the O-ring and re use it. You can use some 3 bond in a few places (just a little ) to hold all O-rings in if you dont have a good o-ring grease handy.

 

[imabadfish]

BR8ES plugs with Aftermarket heads. OEM uses BR8HS (Half Shaft).

you can superglue the oring back together.

Thanks that helps out a lot. Going to pick some up on my lunch break.

BK is correct, the ski will run like crap with BR8HS in there due to lower compresion and spark location to the piston, Advanced has the HARD TOP BR8ES plugs for like $2 ea.. WOW, you had to be super pissed when you bolted this new head on and went to the lake. Use a little 3bond at end of the O-ring and re use it. You can use some 3 bond in a few places (just a little ) to hold all O-rings in if you dont have a good o-ring grease handy.

LOL - yeah I was pretty pissed. The lack of power had me confused too. I used grease last time but I just put the old o-rings in and they seem to fit better that the new ones anyway. I'll pick up some 3bond anyway since its probably handy to have in case i have anymore issues.

I'll torque the head down tonight and try and ride this weekend for a bit. I'll reply with how I got on.

Thanks for the help.