ProwlerJoe

I am getting steam out of my 525EFI exhaust when getting on plane and when coming off plane. This issue just started happening after my ITS install this season. Ran the boat 4 previous seasons and it never steamed out exhaust ever! Pre ITS install: water pressure at idle- 7PSI, mid range RPM 20 PSI, WOT 40PSI. Water temp- Idle- 135-145, WOT- 155 tops after a hard run. Oil temp 185.

Put the ITS box on this year and I am running slightly warmer and getting steam out of exhaust when getting on plane and coming off plane. My water pressure seems low to me at lower RPM, running 3000-3500 RPM it stays around 10-14PSI. Water Pressure at idle- 7PSI, Mid range RPM 10-14RPM, WOT 35PSI. Water temp at idle- 145-150, in 90 degree weather the other day I hit 170. Oil temp is staying at 185.

As a precaution I changed my impeller and same results old impeller was mint, just had very minor scoring on the housing. Looking for input or advice from anyone running ITS and their running specs or anyone that has swapped from a normal HP transom assembly to ITS. I find it very odd that after 4 years I change to ITS and I'm getting steam and running slightly warmer temps. Boat still throws water out of exhaust around 5' at idle so I know it's getting water. I have spoken to a few shops and Mercury Racing direct and they say all number are within normal operating range and there is nothing to worry about. Again, don't understand why the steam now and 15 degree warmer running temp. I have not flushed coolers, but boat has never been plugged up or clogged in muck, only have about 5 hours running time since ITS install. Oil is clean as if it was just changed. Internal sea pump hoses are all straight and unclogged. I can touch CMI headers after a hard run and they are still warm to the touch. While XR is trimmed I can see small bend in hose behind bell housing, assuming that is the water inlet hose going to the stainless fitting through the housing...Curious if that could be my culprit

Thoughts? I would hate to pull all hoses, flush everything then still want to take it to a shop to review, or am I fine with these numbers?
Thanks,
Joe

HyFive578

iTrader: (3)

I have 525's with ITS. My water pressure at idle is 4-6 PSI. Running 3000-3800 RPM water pressure is between 25 and 30 PSI, above 4000 RPM, between 35 and 40 PSI. My water temps are between 150 and 160 all the time no matter how hard I run. oil temp around 185 as well.

The only thing I can think of in your case is that the ITS boxes did something to change the flow into your drives.

ProwlerJoe

Thanks for the feedback. It seems like I get perfectly normal flow at idle and WOT and midrange is the issue. I was thinking the same thing, maybe at 35-55mph the ITS box was causing some air to pass by my pickups, but I am running DWP. I do notice when i trim up water PSI increases. I'm going to check that hose running through the outdrive through the transom...that is the only think I can think of.

BUP

iTrader: (9)

possible water / cracked header issue - excessive steam from the exhaust can be possible internal water leak and or head gasket leak or even possible valve problem along with reversion problems. Also cold mournings hot exhaust can produce steam from the exhaust

HP 525 / headers I would not rule out internal water leak just saying. Not uncommon issue here.

ProwlerJoe

I wouldn't say it's excessive steam, It's just noticeable during take off, dissipates right away. Same with coming off plane, you can see some steam out the back and then it disappears after about 10 seconds of idling. I have heard of the CMI issues, but boat has been fresh water only and the 525 just hit around 300 hours. Oil is extremely clean, pretty positive there are not head gasket issues. Last year put around 50 hours on boat, no steam, ran extremely cool. Motor was pulled to put ITS on during winter, after ITS the steam immediately started and so did the higher running temp. I'm thinking I may have a kink in the intake hose in outdrive? If I had a reversion issue I'm assuming it would steam all the time at idle it doesn't. PSI is on the money at idle at 7PSI and no steam. When I give throttle upon take off the water pressure PSI is not climbing with RPMs as it used to. I feel that it's starving for water during the midrange....

ProwlerJoe

Motor and headers are 2006 as well, just as an fyi, 300 fresh water hours.

papps

Was thinking of doing the ITS swap as well, can you share before and after results speed/handling? And what boat? Thanks

ProwlerJoe

01 Sonic Prowler- 26'. 525EFI, Bravo XZ drive 1.50 ratio. 26LH labbed prop. Boat did not have external hydraulic steering before ITS box. Now it has full IMCO. Boat gets on plane a little quicker, much better handling, better tim-ability, zero chine, stays very level in rough 2-3' chop. Pre-ITS the boat used to launch the bow up at 65MPH+ with tabs up off large waves, now if it gets airborne it is in the air level and lands level. Much safer feeling. I get around 3mph better cruise speed and around 2MPH more WOT. Feels like a completely different boat and looks very clean on the transom. Have only had round 4 hours on it all summer due to a busy schedule, but have seen 74GPS thus far in 1/1/2' chop, right conditions I'm thinking I may be able to see 76. Sonics are very heavy, I'm 5,050 dry, fully loaded with fuel I'm probably 6,000lbs all day.

https://www.youtube.com/watch?v=mXKamwSaQJM

underpsi68

In the video you ran the engine up to 5000rpm in the hose for a bit?

BUP

iTrader: (9)

with a quality prop dyno and a quality contractor grade garden hose you can run any marine engine close or up to for bit to max rpms with no problems. If you do not believe me as I have ran in the 1000's of boat apps this same way, you can also ask Boostpower about doing the same as I am sure he has ran plenty of marine apps up to or over 5 k rpms or very close to it with his builds. I am not saying running the engine to max and leave it there on the dyno / hose .

https://www.youtube.com/watch?v=4y6SC7vaLvY

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