98 115 Ocean Pro (E115SLECM) is it running hotter than it should?

[c6mcfall]

When I got this motor it didn't run, thanks to many on hear my family has been enjoying this rig. I replaced the water pump when I initially got the motor, based on the temp guage at idle speed (no wake) it would creep up to just about the 175 (80 celsius) on the gauge and then drop down to 140-150 up on plane. Last water pump change (18 months ago, less 100hrs) I also did the thermostats. Now at idle it looks like its creeping up just above the 175 (80 celsius) on the gauge but still drops back to 150 (maybe a tad higher). I looked in the shop manual and I don't see anywhere what you should expect as normal operating temp. Would carbon build up contribute?

So planning to do the water pump right away, but was also contemplating doing a vinegar flush. What should I expect for normal operating temp & any feedback on vinegar flush?

Thanks.

 

[Chris1956]

OK, The service manual specifies that with a 70*F water supply, the temp at 900 RPM should be 140*F plus/minus 15*F. At 5000RPM the temp should be no more than 160*F.

​It therefore sounds like you have an issue with the cooling system. Did you install the correct thermostats? I think they are 140*F. At idle, these control the water temp.

​At high speed the water pressure should push the 'stats of their seats allowing water to bypass them. Are your thermostat springs the correct ones?

 

[c6mcfall]

Thanks for the reply, I believe they're the correct ones.. I did order them (OEM) but I'll have to pull them this weekend and check to be 100% assuming they have part number stamped on them?

 

[bob johnson]

I chased a 180 idle temp on one bank of my ocean runner 115 for years.... I did everything I could find info on.... nothing worked.. until I put a weak t-stat spring in...to allow less water pressure to push the t-stat off the seat.. It is possible salt build up could have blocked some of the passages.... the opening in the t-stats are just so small . but you know if one side is hotter its a fixable problem.... you look at the lean mixture, you look at individual components like seals and t-stats, and cylinder head blockage,.... I found out on my recent outboard install ( 1999 ocean pro 150 hp) that my temp gauge was reading wrong!! and I had one for each head.... apparently the sender didn't match the guage of ohms resistance...so the gauge was reading about 20 degrees high! the service tech verified it with an infared thermometer while running in his shop.... so that's one thing to check.....get an infared thermometer and see if the head reads what the gauge is saying

 

[boobie]

Agree, you may have a bad temp gauge. Check your motor with a temp gun.

 

[clanton]

60 degree engine?????? Make sure you have the correct waterpump housing.

 

[c6mcfall]

Thanks I'll check with temp gun, kicking myself for not doing that today.. I pulled the t-stats, put alarge tub under the lower unit, rigged a bilge pump up from the tub to the flush port. Ran a coninues flush of 50/50 vinegar & water for a few hours. The water looked nasty after, flushed with dawn for 20 min to neutralize, then fresh water. One thing I noticed, one of the t-stats rattled if I shook it and one didn't.. could one of them be stuck. Just because they are newer (@ 6 months) doesn't mean they're good..

 

[Chris1956]

I would not expect the 'stats to rattle.

I just replaced mine (s/b same ones), because you could blow thru them when they were closed. My motor would not warm up, on cold days....

 

[bob johnson]

Thanks I'll check with temp gun, kicking myself for not doing that today.. I pulled the t-stats, put alarge tub under the lower unit, rigged a bilge pump up from the tub to the flush port. Ran a coninues flush of 50/50 vinegar & water for a few hours. The water looked nasty after, flushed with dawn for 20 min to neutralize, then fresh water. One thing I noticed, one of the t-stats rattled if I shook it and one didn't.. could one of them be stuck. Just because they are newer (@ 6 months) doesn't mean they're good..

I guess a spring could have broke inside........

 

[c6mcfall]

I guess a spring could have broke inside........

So if the spring broke, would that make it open prematurely or not at all? Obviously I'll replace both a 2nd time, glad I spent the extra $$ for OEM T-Stats..

Dare I ask, what about Sierra T-Stats?

 

[oldboat1]

think you should get points for the creative flushing exercise for salt buildup -- have to believe that could be key. Hope you post back.

Don't recall experience with Sierra stats (seems to me I have a Mallory stat in my inboard, though, and that has been fine). Probably smart to just test out any stat you buy just to make sure it opens at its specified temp.

 

[bob johnson]

So if the spring broke, would that make it open prematurely or not at all? Obviously I'll replace both a 2nd time, glad I spent the extra $$ for OEM T-Stats..

Dare I ask, what about Sierra T-Stats?

id think...not at all..... sierra should be fine...... my guess is the same manufacturer makes the T stats for both Sierra and BRP...

 

[c6mcfall]

Will replace both T-Stats and water pump and report back. Thanks for the help.

 

[c6mcfall]

Got all my parts but the T-Stats. Pulled lower unit, water pump looked good, not much wear.. Nothing obviously wrong with pump. Replace the water pump (changed lower unit oil too while I was at it) and here are the results

Fired right up on muffs, let it run @idle.. temp ran up got to 140 then seemed to hold @ 150 on gauge (before was ~ 170/180)

I checked block with a laser thermometer:

- Head with the non-rattling T-stat Temp was 149-151 depending on where I aimed
- Head with the rattling T-stat, temp was 119-121 degrees depending on where I aimed (have to think that the spring is broken)

Didn't bother swapping them and testing, will just replace with new and test and post results.

 

[c6mcfall]

Expecting my T-Stats tomorrow but had another question.

Ever since I had this motor anytime I'd take it out run it and come back and flush. I'd always have the notorious 2 stroke oil "bleed" and it be dripping on the driveway the next day.. I know I'm not the only one that has experienced this I've seen many people ask about it. I didn't think much of it but when i walked by the boat this morning I noticed I didn't have this after using it this weekend.. Honestly don't know what to make of it..

 

[Chris1956]

2 cycle oil should not normally drip from the motor, IMO. The flushing process should carry away an unburnt oil. A drip the next day could be from carb drippage due to incorrect float height, bad gasket, warped bowls or non-sealing inlet needles.

In your case, maybe your inlet needles are sealing better, than before?