192 Heat Soak After IC swap

[JHall]

did a lot of reading, and it looked like everyone who upgraded to an SVHO IC had eliminated heat soak. I did the swap last week and im still having heat soak issues in a bad way. 5 minutes of WOT if im lucky, and im back down to 7100-7200 RPM and 40mph. Any recommendations? Really want to fix this.


Just to add, there is a good stream coming out both ports, engine has about 15 hours on it. Hits 7800 initially, then just slowly creeps down to 7200 or so. I run the fan and idle for a while to cool off, then after hanging in a cove for a while, it’ll go back to 7800 but the hotter the temp outside, the quicker it backs off.

 

[SamCF]

did a lot of reading, and it looked like everyone who upgraded to an SVHO IC had eliminated heat soak. I did the swap last week and im still having heat soak issues in a bad way. 5 minutes of WOT if im lucky, and im back down to 7100-7200 RPM and 40mph. Any recommendations? Really want to fix this.

Dedicated cooler line and high flow strainer.

 

[JHall]

Dedicated cooler line and high flow strainer.

So plug the factory cooler line and run one through the hull to a tapped strainer like Riva sells? As much as I don’t want to, I will if that will fix it. It’s so frustrating. Really wish I’d read about the heat soak before I bought it. Love it otherwise

 

[SamCF]

So plug the factory cooler line and run one through the hull to a tapped strainer like Riva sells? As much as I don’t want to, I will if that will fix it. It’s so frustrating. Really wish I’d read about the heat soak before I bought it. Love it otherwise

Yeah. Some have said the high flow strainer is just as important as the dedicated line. I just enlarged the holes in my factory strainer. Use the existing hole in the hull for the clean out tray drain.

 

[REM835]

Maybe dumb question but would hi flow strainer help anything without doin the 2nd dedicated line?

@JHall what is the outside temp and lake temp your running in? Did you pull the manifold when you installed the IC?

 

[JHall]

Maybe dumb question but would hi flow strainer help anything without doin the 2nd dedicated line?

@JHall what is the outside temp and lake temp your running in? Did you pull the manifold when you installed the IC?

It has been in the 90’s here. And water temp mid 80’s. I did not pull the manifold. I thought about doing the ribbon delete but read most people not experiencing any gains other than throttle response.

 

[REM835]

It has been in the 90’s here. And water temp mid 80’s. I did not pull the manifold. I thought about doing the ribbon delete but read most people not experiencing any gains other than throttle response.

That’s right...I have three projects on deck and got it all confused. I have all the parts to do everything but am scared to screw it up before a family trip next weekend.

 

[JHall]

That’s right...I have three projects on deck and got it all confused. I have all the parts to do everything but am scared to screw it up before a family trip next weekend.

The IC swap took all of 10 minutes. Took longer to find a tee than it did to do the swap. Apparently Lowe’s doesn’t carry 5/8 wyes or tees, so I had to get one on amazon.

 

[haknslash]

How hot is the temp coming from the intercooler pisser? It should not be hot like the engine pisser.

In the middle of the summer I will see the RPM drop down to maybe 100 rpm less but my top speed remains 48-49 on the gauge. If anyone is in the bow you can expect it to drop considerably. Are you alone on the boat and getting those numbers? Clamps tight? I know when I first installed mine one of my clamps blew off and performance tanked from the big boost leak.

 

[JHall]

How hot is the temp coming from the intercooler pisser? It should not be hot like the engine pisser.

In the middle of the summer I will see the RPM drop down to maybe 100 rpm less but my top speed remains 48-49 on the gauge. If anyone is in the bow you can expect it to drop considerably. Are you alone on the boat and getting those numbers? Clamps tight? I know when I first installed mine one of my clamps blew off and performance tanked from the big boost leak.

You were my inspiration in doing this lol. Pisser is about lake water temp. Maybe a touch higher but nothing like the engine cooling pisser. It was me, my son, and my twin girls. Maybe 500lbs of us. Everyone in the back. Double checked clamps. It’s doing exactly the same as it did before the swap, except maybe holding higher rpms just a bit longer initially.

 

[haknslash]

It doesn't show on your profile but where are you boating? I'm in the south so it's very hot and humid here. Are you by chance at elevation?

I'm sorry the SVHO swap isn't showing any signs of improvement. It most certainly should as it has helped several of us on here. I wonder if your IC core is corroded or something. Do you know if it came from a salt water use PWC? The SVHO swap helps get rid of most of the heat soak but the larger the intercooler the better it works. They also say a dedicated cooling line and high flow strainer can be just as effective as the IC swap but I never went that far since I wanted to do it in phases and only upgrade if I felt the need to. Since the IC swap solved 98% of the issue for me I stopped modding there (aside from the ribbon delete which didn't do much for me as you know). Maybe you live in a climate that needs both the IC upgrade and a dedicated cooling line but I would think my climate would also show I need those mods and that hasn't been the case although I wouldn't mind a dedicated line just to maybe squeeze me to 50 mph (gauge indicated) instead of 48-49 mph.

 

[JHall]

It doesn't show on your profile but where are you boating? I'm in the south so it's very hot and humid here. Are you by chance at elevation?

I'm sorry the SVHO swap isn't showing any signs of improvement. It most certainly should as it has helped several of us on here. I wonder if your IC core is corroded or something. Do you know if it came from a salt water use PWC? The SVHO swap helps get rid of most of the heat soak but the larger the intercooler the better it works. They also say a dedicated cooling line can be just as effective but I never went that far since I wanted to do it in phases and only upgrade if I felt the need to. Since the swap solved 98% of the issue for me I stopped modding there (aside from the ribbon delete which didn't do much for me as you know). Maybe you live in a climate that needs both the IC upgrade and a dedicated cooling line but I would think my climate would also show I need those mods and that hasn't been the case although I wouldn't mind a dedicated line just to maybe squeeze me to 50 mph (gauge indicated) instead of 48-49 mph.

Central ky... not at any elevation worth noting. And the IC was off a new ski from Riva. It was apparent it had never seen water. I’d love to do the mods to get 60+, but considering this boat has maybe 15 hours on it and is early in its warranty, I’d hate to screw that up

 

[haknslash]

Well @SamCF is definitely the guy you want to talk to about reaching those speeds in your boat. His boat flat out flies!!

I'm sure the climate in KY is very similar to AL, maybe a hair less humidity there since it might not be as subtropic climate like it is here. You honestly shouldn't have any issues with that swap and should be seeing most of your heat soak gone, so I'm puzzled why it's literally performing like your smaller stock IC was with performance fading away so soon from a cold start. The SVHO part number did check out correct?

You IC pisser should be about the same temp was what the water temp is. Ever since my swap mine has been that way and the engine is always the one that is hot. When using the stock intercooler it is practically scalding hot for the IC pisser, so at least you know it is working to some degree. I just don't see why it isn't helping you at all from the performance. In the dead of summer I think my boat settles in around 7500 rpm on super hot days but top speed is rarely affected. I haven't been out on my boat in a few weeks but I'll take some new RPM and top speed readings next time I'm out.

 

[JHall]

Yep, and it’s nesrly twice as big. Has dual outlets. Definitely the right part. And has a good stream out the pisser so it’s getting good flow. I’m going to change the plugs just for good measure. No clue if they’ve ever been changed. I can’t imagine they’d cause that issue though. This pic is where it settles after a few minutes of WOT... it’ll hit it religiously after it warms up, but can only go higher when it’s cooled off significantly.

 

[haknslash]

Yea something is not right about that. 7100 RPM and 40-ish mph is definitely heat soak like the stock intercooler. Maybe do another good check on the clamps and hoses, especially the one below the intercooler going to the throttle body. Make sure that hose is pushed all the way against the intercooler to where the rubber hoses touches the little tab on the casting of the intercooler.

Changing the plugs isn't a bad idea. I don't think it's the issue but you never know with these engines as they can be finicky with less than great condition plugs. Worth a shot.

At least we both get the condensation in the gauges like everyone else

 

[JHall]

Yea something is not right about that. 7100 RPM and 40-ish mph is definitely heat soak like the stock intercooler. Maybe do another good check on the clamps and hoses, especially the one below the intercooler going to the throttle body. Make sure that hose is pushed all the way against the intercooler to where the rubber hoses touches the little tab on the casting of the intercooler.

Changing the plugs isn't a bad idea. I don't think it's the issue but you never know with these engines as they can be finicky with less than great condition plugs. Worth a shot.

At least we both get the condensation in the gauges like everyone else

I was wondering about that. I only recently started noticing it. And only on the tach. Annoying! Lol

Now just tell me I’m not the only one that pulls to the lake like this...

 

[haknslash]

Wow!!! That is one helluva way to arrive at the ramp!!!

Yup usually the tach fogs for me. I think it's because of the buttons allowing for some difference in humidity inside the gauge vs outside. Being on the water we have a natural moisture in the air so I think some of it makes it's way in the gauge and then has an imbalance, sort of like your car window does on mornings with A/C running and condensation forms on the glass. I don't know just speculating but it's a common thing/annoyance with many Yamaha boats for several years. I once did a search on it long ago and came to the conclusion it's 'normal' lol.

 

[Midnight2V]

[QUOTE="]You were my inspiration in doing this lol. Pisser is about lake water temp. Maybe a touch higher but nothing like the engine cooling pisser. It was me, my son, and my twin girls. Maybe 500lbs of us. Everyone in the back. Double checked clamps. It’s doing exactly the same as it did before the swap, except maybe holding higher rpms just a bit longer initially.[/QUOTE]


Important question, was this svho intercooler a new take off or used? If used was it in fresh or salt water?

At idle there should not be any real temperature difference because the supercharger is not generating any boost. If it is much hotter than ambient air at idle, that is the residual heat in the metal of the intercooler or the supercharger housing that is being transferred to the water, which is a telltale sign of heatsoak. Carefully check your pisser while at high speed. It is at high rpm and under boost that the intercooler is pulling heat from the compressed air charge, that's when it should be hot. If your pisser is still cool, then one of two things is likely. You could have corrosion or fouling of the intercooler, in which case it is not pulling heat from the air charge. The other possibility is a small boost leak, in which case you should check all your connections.

Also check your intercooler's shell temperature at WOT after a run at WOT of at least 10 mins or until you get rpm limited. It may be warm but should not be hot. If it is extremely hot, it is either heatsoak due to insufficient cooling water, or is not transferring heat to the water. Now check the water outlet. If it is hot, you need more water flow. If is cool your intercooler is not doing its job. My cooler flow outlet is never more than about 110F even after 30 minutes of WOT. Maybe a little hotter than that if the water was already in the 90's.

If you have a boost leak, then neither the intercooler shell, nor the water stream will be hot since there is no heat being generated due to a lack of air pressurization.

 

[JHall]

Important question, was this svho intercooler a new take off or used? If used was it in fresh or salt water?

At idle there should not be any real temperature difference because the supercharger is not generating any boost. If it is much hotter than ambient air at idle, that is the residual heat in the metal of the intercooler or the supercharger housing that is being transferred to the water, which is a telltale sign of heatsoak. Carefully check your pisser while at high speed. It is at high rpm and under boost that the intercooler is pulling heat from the compressed air charge, that's when it should be hot. If your pisser is still cool, then one of two things is likely. You could have corrosion or fouling of the intercooler, in which case it is not pulling heat from the air charge. The other possibility is a small boost leak, in which case you should check all your connections.

Also check your intercooler's shell temperature at WOT after a run at WOT of at least 10 mins or until you get rpm limited. It may be warm but should not be hot. If it is extremely hot, it is either heatsoak due to insufficient cooling water, or is not transferring heat to the water. Now check the water outlet. If it is hot, you need more water flow. If is cool your intercooler is not doing its job. My cooler flow outlet is never more than about 110F even after 30 minutes of WOT. Maybe a little hotter than that if the water was already in the 90's.

If you have a boost leak, then neither the intercooler shell, nor the water stream will be hot since there is no heat being generated due to a lack of air pressurization.

It was a new take off from Riva. Didn’t appear to have ever been in the water. I will check these things. That’s good info

 

[Jetswu87]

5 minutes of WOT is a lot if that is truly the case, how many of you guys go wide open for that long? I don't think there's anyway the boat isn't going to build IAT temps in 80+ Degree water temps.

Do you notice if you come back and cruise at say 25-30mph for a bit, the speed power will come back?

Surface water temps for here are in the high 80's and air temp in the 90's, I've noticed going WOT after cruising I'm seeing 7350rpm max but it'll hang around 7200-7300 shortly there after. Boat is still doing 44-45mph though on GPS. Two people and a 70lb dog. SVHO intercooler.

I've had some glory runs in the morning, high as 51....typically around 48-49. Boat empty.