Overheating and clearing or flushing cooling lines

[r3cc0s]

Fixed fuel issue (water) and my engine was overheating, as I likely had issues while I was troubleshooting my boat in shallow water... may have took in sand or gravel through the jet

first off... jet seems to be in good shape, but the pisser wasn't really giving a good stream at high rpm and then I started seeing smoke from the exhaust

So I decided to "flush"

I have the diagram from the manual

I attached the hose using a flush fitting

with just the engine started and it attached, without hose clamps, there is water coming out of the hose from the other side of the head (to the back of the boat), the exhaust, the jet and the pisser

when I use the hose clamp, the pisser increases alot as the water is capped off from the other side of the head, and more water comes out of the jet and the exhaust (good)

I just don't know if I've cleared the issue 100% as I wasn't able to tell what debris came out of the engine or if not

"IF" I took in more than sand, say pebbles... will it get into my exhaust or head easily, or will it be more jammed in the lines?

The line from the jet, seems to go to a T section that I think goes to both the bottom of the block and the exhaust, is that where I start first?

 

[r3cc0s]

really? no help here? nobody's had this problem?

I took it out for a ride and again same thing... when I flush, the hose that goes to the exhaust is "full" and comes out, as does the pisser... but when I use the boat, using its jet, the hose has air gaps in it.

 

[tobytd]

I dont have a boat (PWC) but I would pull hoses & use a little compressed air to make sure all hoses and passage ways are clear - open If no air try water hose MAKE SURE
you dont flood engine thru the exhaust

 

[r3cc0s]

I dont have a boat (PWC) but I would pull hoses & use a little compressed air to make sure all hoses and passage ways are clear - open If no air try water hose MAKE SURE
you dont flood engine thru the exhaust

thanks, we are going to use a wire and compressed air to clear the fittings and hoses...

any guidance or advice on how to clear the passages through the exhaust/tuned pipes if necessary?

 

[Steelmesh]

My tell tale "pisser" was not flowing, I used compressed air to jettison something blocking. I pulled that weep/pisser tube off the T- from inside the boat and blew it from inside out. I say see if debris is an issue, then I recommend also pulling the valve cover and see how bad it is in there.

 

[r3cc0s]

My tell tale "pisser" was not flowing, I used compressed air to jettison something blocking. I pulled that weep/pisser tube off the T- from inside the boat and blew it from inside out. I say see if debris is an issue, then I recommend also pulling the valve cover and see how bad it is in there.

so... when I hook up the flush fitting, the "pisser" is moving, and if I clamp the line, the pisser shoots almost a couple feet, which means the heads should be clean right?

 

[racerxxx]

What line are you clamping? The fat one on the right side of the head ----if you're looking at the engine from behind it?




Here is your cooling diagram. The 95 Sportster came up a twin engine or a single?

 

[r3cc0s]

What line are you clamping? The fat one on the right side of the head ----if you're looking at the engine from behind it?




Here is your cooling diagram. The 95 Sportster came up a twin engine or a single?

this is correct #4 or the "fat" tube that leaves the boat

 

[r3cc0s]

this is correct #4 or the "fat" tube that leaves the boat

Guys I really need some help... my mechanic has ran compressed air and a wire through all the fittings and water will still not come in through the jet.

Verified the jet assembly and wear ring is good.

He is speculating that there isn't a vacuums from the exhaust as the water pump isn't the only pressure that feeds the line and that maybe there is a an air leak or with the gasket in the exhaust chamber...


I'm going to order a gasket kit for the engine but can anyone confirm whether this is the right process and if there is a vacuum from the exhaust that draws the water through it?? Thinking about it, I don't think any vacuum draws the water through the heads right?

 

[2x2smoke]

To sum things up, your boat pisses on the hose but not out on the lake and it overheats?

I wouldnt trust anything from your mechanic at this point given the exhaust vacuum confusion.

You can pull your pump to verify that all 4 holes inside are unobstructed as a starting point. If 3 out of 4 holes are plugged it would still allow compressed air to pass while not providing enough water though under working conditions. Maybe its possible to just remove the nozzle and use a mirror to look at the holes if you don't want to fool with the driveshaft etc you should get water gushing out 4 holes inside the pump when you flush retrograde.

Its not obvious in the diagram above where the water enters the block. It looks like the pump flows only into the head pipe so maybe the block only gets flow from the head pipe via the manifold.

 

[K3ROK]

Fixed fuel issue (water) and my engine was overheating, as I likely had issues while I was troubleshooting my boat in shallow water... may have took in sand or gravel through the jet

first off... jet seems to be in good shape, but the pisser wasn't really giving a good stream at high rpm and then I started seeing smoke from the exhaust

So I decided to "flush"

I have the diagram from the manual

I attached the hose using a flush fitting

with just the engine started and it attached, without hose clamps, there is water coming out of the hose from the other side of the head (to the back of the boat), the exhaust, the jet and the pisser

when I use the hose clamp, the pisser increases alot as the water is capped off from the other side of the head, and more water comes out of the jet and the exhaust (good)

I just don't know if I've cleared the issue 100% as I wasn't able to tell what debris came out of the engine or if not

"IF" I took in more than sand, say pebbles... will it get into my exhaust or head easily, or will it be more jammed in the lines?

The line from the jet, seems to go to a T section that I think goes to both the bottom of the block and the exhaust, is that where I start first?

Hey guys,

I am having a similar issue and it just noticed I wasn't getting any water out of the "pisser/ski tow" hole on a 1998 Challenger (Twin) when moving at slow speed in the water.

We are on a really really weedy lake and I find myself constantly having to pull weeds out from under the boat wrapped around the drive shaft blocking the impeller.

If I am moving slowly the weeds seem to collect even more and eventually the overheat alarm will go on. After removing the weeds and letting the engine cool a bit I fire it back up and everything seems to work great for hours at top speed and the overheat alarm doesn't come back on, but... I didn't notice any water coming out of the hole?!

A few questions:

1. Wouldn't the overheat alarm come on really quick if there was no water coming through indicating a problem?
2. Should I do a flush to check the system anyways? Possible for a zebra mussel or debris has clogged the system?
3. Where exactly is the inlet to draw water in to cycle through the engine?
4. I didn't notice top and rear engine flushing fittings, just the ones at the top. It it possible this model only has the top fitting without the "T" in the hose to the 2nd one like the manual suggests?

I would greatly appreciate any pointers and thanks in advance... Also, any suggestions on dealing with the WEEDS would be awesome as the weedless lever just doesn't work all that well.

Cheers!

 

[r3cc0s]

To sum things up, your boat pisses on the hose but not out on the lake and it overheats?

I wouldnt trust anything from your mechanic at this point given the exhaust vacuum confusion.

You can pull your pump to verify that all 4 holes inside are unobstructed as a starting point. If 3 out of 4 holes are plugged it would still allow compressed air to pass while not providing enough water though under working conditions. Maybe its possible to just remove the nozzle and use a mirror to look at the holes if you don't want to fool with the driveshaft etc you should get water gushing out 4 holes inside the pump when you flush retrograde.

Its not obvious in the diagram above where the water enters the block. It looks like the pump flows only into the head pipe so maybe the block only gets flow from the head pipe via the manifold.

okay...

so I'm going to order a gasket kit, because the exhuast manifold gasket has a tendency to break... but to confirm...

Is there any vaccuum at all that would "suck" water into the water jackets? Otherwise, really the guy needs to do what aforementioned and that is continue to flush the fittings, and the exhaust/tuned pipe?

What do you mean about 4 holes inside the pump? are you refering to the pisser/tow hook? If so I have a sportster, which means only one side of engine.

Water goes through the head well, as through the "hose" water comes through the pisser

So that to me means that the issue is where the water enters the jet and then the T connector or within the exhaust itself.

 

[racerxxx]

okay...

so I'm going to order a gasket kit, because the exhuast manifold gasket has a tendency to break... but to confirm...

Is there any vaccuum at all that would "suck" water into the water jackets? Otherwise, really the guy needs to do what aforementioned and that is continue to flush the fittings, and the exhaust/tuned pipe?

What do you mean about 4 holes inside the pump? are you refering to the pisser/tow hook? If so I have a sportster, which means only one side of engine.

Water goes through the head well, as through the "hose" water comes through the pisser

So that to me means that the issue is where the water enters the jet and then the T connector or within the exhaust itself.

Don't order a gasket kit, if yours isn't leaking you're just wasting money. You're gaskets shouldn't just break, I've never had one break in 20 years of messing with Seadoo's unless I took something apart and it stuck and broke apart while removing components.

You need to just get the boat back and work on it yourself.

Here's an easy test, go to the body of water you ride in, back the trailer in the water...............leave it on the trailer. Follow the line that comes from the pump and goes to the front of the pipe. Disconnect that line from the pipe. Start the engine, water should be flowing from that hose. Make sure the pump is fully in the water and leave the boat strapped down. If no water is coming out of that line you need to pull the pump. As mentioned before there are 3 or 4 holes in the pump for the water inlet (that feed the line I'm talking about) if those are blocked or partially blocked you will not get enough water flow plain and simple, you need to pull the pump to see them. The blades of the impeller push the water into the pump housing and thru the engine. Lets verify were actually getting water thru the pump. I don't care what is coming out when you run it on the hose, you're backfeeding the system on the hose....that's not where you're having an issue. So, if no water comes thru that line you could then undo the hose clamp and remove the line directly from the pump inlet tube and see if water is coming in......if no water is coming in then you pump definitely is obstructed. If water IS coming out the line then we have issues other places that we need to find.

 

[racerxxx]

Hey guys,

I am having a similar issue and it just noticed I wasn't getting any water out of the "pisser/ski tow" hole on a 1998 Challenger (Twin) when moving at slow speed in the water.

We are on a really really weedy lake and I find myself constantly having to pull weeds out from under the boat wrapped around the drive shaft blocking the impeller.

If I am moving slowly the weeds seem to collect even more and eventually the overheat alarm will go on. After removing the weeds and letting the engine cool a bit I fire it back up and everything seems to work great for hours at top speed and the overheat alarm doesn't come back on, but... I didn't notice any water coming out of the hole?!

A few questions:

1. Wouldn't the overheat alarm come on really quick if there was no water coming through indicating a problem?
2. Should I do a flush to check the system anyways? Possible for a zebra mussel or debris has clogged the system?
3. Where exactly is the inlet to draw water in to cycle through the engine?
4. I didn't notice top and rear engine flushing fittings, just the ones at the top. It it possible this model only has the top fitting without the "T" in the hose to the 2nd one like the manual suggests?

I would greatly appreciate any pointers and thanks in advance... Also, any suggestions on dealing with the WEEDS would be awesome as the weedless lever just doesn't work all that well.

Cheers!

K3ROK,

Welcome to the forum, if you haven't done so yet, please start your own thread with your problem. We don't want to suggest thing to 2 members in one thread, it can get confusing for the original poster and us.

Thanks!

 

[2x2smoke]

pic of the inlet holes in the pump "pressure zone".
http://www.seadoosource.com/images/wearring4.jpg

pic of the 657 coolant flow for a ski
http://www.pwctoday.com/showthread.php?t=160294&p=1582052&viewfull=1#post1582052

circulation: jet pump pressure zone-headpipe-manifold-cylinder block-cylinder head-outlet hose

Vacuum question: I guess its true that exhaust gasses flowing through the pipe might suck water out of the water injection fittings. (venturi effect)

All 3 of these fittings on your engine are placed at points upstream to where water enters the block and cylinder head. Any vacuum effect would be to suck water out of the block in the wrong direction. mechanic's explanation/theory doesnt hold water

 

[K3ROK]

K3ROK,

Welcome to the forum, if you haven't done so yet, please start your own thread with your problem. We don't want to suggest thing to 2 members in one thread, it can get confusing for the original poster and us.

Thanks!

Sorry about that. I will start a new thread.

 

[r3cc0s]

Here's an easy test, go to the body of water you ride in, back the trailer in the water...............leave it on the trailer. Follow the line that comes from the pump and goes to the front of the pipe. Disconnect that line from the pipe. Start the engine, water should be flowing from that hose. Make sure the pump is fully in the water and leave the boat strapped down. If no water is coming out of that line you need to pull the pump. As mentioned before there are 3 or 4 holes in the pump for the water inlet (that feed the line I'm talking about) if those are blocked or partially blocked you will not get enough water flow plain and simple, you need to pull the pump to see them. The blades of the impeller push the water into the pump housing and thru the engine. Lets verify were actually getting water thru the pump. I don't care what is coming out when you run it on the hose, you're backfeeding the system on the hose....that's not where you're having an issue. So, if no water comes thru that line you could then undo the hose clamp and remove the line directly from the pump inlet tube and see if water is coming in......if no water is coming in then you pump definitely is obstructed. If water IS coming out the line then we have issues other places that we need to find.

Thanks!

racerxxx thanks for the advice...

Mechanic is at my lake and not here, but I passed this along and he said that the 3 little holes at the top is not plugged as water is coming to the T connector...

he thinks the tunedpipe/exhaust is plugged, so he is ordering one from BRP

 

[r3cc0s]

thanks 2x2smoke

you guys are right, there shouldn't be any "vacuum" and its likely everything is plugged up inside of the exhaust/tuned pipe as the hose/flush fitting seems to flow very well through the cylinder head...

the mechanic just can't seem to get the tuned pipe/exhaust cleared, and the gasket ripped on removal, which is why I needed to order a new kit

so new kit, new tuned pipe, and problem should be solved?? may need some new hoses as well.

 

[r3cc0s]

man...

so mechanic has "cleared hoses", used a gasket kit and replaced the O'ring after cleaning out the head water jacket, replaced the tuned pipe and exhaust manifold and still on the water, nothing is coming out of the pisser, yet it does piss if the "vent fitting" is on.

Chances are at this point, only the 3 little holes on the Jet is plugged I guess?

man this is taking alot of labor and parts... I may have to replace the entire jet assembly I've been told

 

[2x2smoke]

Ok I re read the history. 1st post says water coming out of the jet when hose is attached to the flushing port. Even more water when the large outlet hose is pinched off. This means that at least one of the three holes inside the jet pump is clear. Its still possible that the other two holes are blocked.

You can observe these holes up through the nozzle without taking anything apart. Is water flowing out of all three when backflushing the motor?

you can also just pull the jet pump off to inspect that water passage by only having to remove about 6 nuts in about 5 minutes time. Has your mechanic done this?

If all your passages are clear then maybe your low water pressure is caused by worn wear ring/impeller. Easy to measure and inspect to see if this might be the issue. Does your boat have major cavitation or propulsion issues as well? These issues might require the rebuilding of the jet pump but not necessarily replacement.

There must be some sort of communication breakdown to explain all the erroneous info your mechanic is feeding you. I've only been interested in sea doos for 60 days and I'm running rings around this guy.:cheers:

 

[r3cc0s]

Ok I re read the history. 1st post says water coming out of the jet when hose is attached to the flushing port. Even more water when the large outlet hose is pinched off. This means that at least one of the three holes inside the jet pump is clear. Its still possible that the other two holes are blocked.

You can observe these holes up through the nozzle without taking anything apart. Is water flowing out of all three when backflushing the motor?

you can also just pull the jet pump off to inspect that water passage by only having to remove about 6 nuts in about 5 minutes time. Has your mechanic done this?

If all your passages are clear then maybe your low water pressure is caused by worn wear ring/impeller. Easy to measure and inspect to see if this might be the issue. Does your boat have major cavitation or propulsion issues as well? These issues might require the rebuilding of the jet pump but not necessarily replacement.

There must be some sort of communication breakdown to explain all the erroneous info your mechanic is feeding you. I've only been interested in sea doos for 60 days and I'm running rings around this guy.:cheers:

its like this...

using the hose fitting, I see a small stream of water coming out of the pisser (tow hook) from the small clear line from the head, and tons of water out of the big line that comes out of the head.

You are supposed to then pinch that big hose to get water to back wash out through the exhaust manifold into the tuned pipe and back also out through the fitting where it comes in from the Jet into both the tuned piipe and exhaust manifold

the mechanic said that the Jet was fine, and the blockage was in the tuned pipe/exhaust, which I've replaced, as well as replaced the gasket and also opened up the head to wash out any sand in the water jacket in the head (requiring a new o-ring)

he is now telling me that its both the Jet and the exhaust manifold that now needs to be worked on or replaced.

 

[2x2smoke]

man...

so mechanic has "cleared hoses", used a gasket kit and replaced the O'ring after cleaning out the head water jacket, replaced the tuned pipe and exhaust manifold

he is now telling me that its both the Jet and the exhaust manifold that now needs to be worked on or replaced.

Did he replace the headpipe and the tuned pipe and now wants to replace the exhaust manifold?

The tuned pipe doesn't have a water jacket that could get clogged if I understand the diagrams. Is this your understanding? If so, I question the need to replace that component.

 

[r3cc0s]

Did he replace the headpipe and the tuned pipe and now wants to replace the exhaust manifold?

The tuned pipe doesn't have a water jacket that could get clogged if I understand the diagrams. Is this your understanding? If so, I question the need to replace that component.

yes, because it turned color he thought the blockage was there. He replaced the tuned pipe and exhaust manifold, leaving the "muffler" or "water box" in place as water is coming out of the exhaust off the back of the boat

The water jackets are cleaned out on the Heads

Now that it is still occurring, he believes its upstream of that now, where it must be the exhaust manifold that attaches to the tuned pipe and possibly the Jet, which he has a fully rebuilt jet with a new impeller/wear ring cone etc..

So new jet, new tuned pipe, new exhaust manifolds and cleaned heads is apparently the fix for a bit of sand ;(

 

[2x2smoke]

Looks like what I call the head pipe (787 engine) is called a tuned pipe on yours. That part does have a jacket. The section called cone pipe (both engines) is the one without any jacket.

Regardless, I hope that you have a fixed up boat by the weekend.

 

[r3cc0s]

Boat is fixed.

Ends up the Jet holes were all scraped shut with plastic overlap when I sucked in a bunch of gravel and stones when I got pushed into the shore by a big malibu while trying to get my engine started

Needed to replace the Jet, so put in a new impeller and wear ring, cone while I was at it.

So to fix this cooling issue...:

Pulled the heads to clear the sand out of the jugs
Replaced tuned pipe and Exhaust manifold
Replaced Jet and assoicated components


not sure why Seadoos are so complicated and expensive to fix their cooling systems