'96 225 Promax temp/PSI ???

[Allyfishing]

Hello gentlemen...I am having an issue with a fresh rebuild 96 225 PM. Started it up for the first time on Sun and let it idle a while to warm up. No reading on the temp gauge so I suspect it to be the temp sensor on the port head. I know my gauge works. Checked with laser temp gun and port head is 116* and starboard head is 165*+/-. It pees real strong at idle but when I whack the throttle a few times it stops peeing. I check temp again with gun and port side 96* and starboard is 126. After a short time is starts peeing again. All reading are at the same spot on each head just below the top spark plug on each side.

Also at idle the PSI gauge is reading around 12-14PSI. I read in the Merc Manual that at idle it should be 3 PSI +/-. I did a search here and on S&F and came up with something about a poppet valve issue and or adapter plate issue.

Any insight or help is greatly appreciated. I don't want to lake test til I know I have the correct PSI and temp gauge iws working. I ordered a new temp sensor but am concerned with the big differrence in temp between the 2 heads.
Thanks for looking and any help in advance.
Craig

 

[bruce pitts]

what temp does your gauge start at 1st i would check the theromstats to see if they are work right theyshould be 140 on the temp before they off you can heat so water in a pan up to 150 and ease it down in the hot water and it should open then put it in some cool water to see if it closes all the way to plus i would back it in the water at the lake

 

[h2oskiier30]

Are you running a one or two piece adapter plate? There are lots of people who have problems with cooling on ProMax's (or any poppit valve motors, for that matter) while trying to run a one piece plate. Of course, there are a few who claim to do it with no problems whatsover.

 

[Allyfishing]

I don't know about the adapter plate, that's something I'll have to ask the builder. The thermostats are new but I will check them tonite in hot water and a thermometer. I took the poppet valve apart this morning (what a my mom) but could not find anything obvious. Thanks for the replies.
Craig :at the bar

 

[Allyfishing]

I ran it on the hose again today for about a half an hour. I set the idle to about 750-800 RPM's according to the tach. It idles on the hose at 10PSI. The port head temp was 122 and the starboard was 168. Like before, hit the throttle a few times and rev it up let it settle and temp drops to just under 100 on the port sie and 135 starboard side.

I'm taking it to the lake tomorrow to just putt putt around and get some brake-in time but I am concerned about engine temp. I have a temp sensor ordered then I'll be able to at least watch the gauge.

Any other input will be appreciated. I am waiting to hear from the builder if a one piece or two piece adapter plate was used.
Thanks
Craig :very sad

 

[bruce pitts]

i glad to here you are going to the lake a hose just don't work for me when i tune or or fire up a new rebuild i allways go to the big water just back it in and leave it hook up let the lower be under water leave the top off fire it up let it warm up wack it a a little and check the head temp make sure that the temp sensor in all the way in the head it's got to be against the head and make sure the end of the sensor is clean and inside the head

 

[Allyfishing]

Well I found out it is a 2 piece adapter. That's good.

Made it to the lake today and idling warmed up on the trailer just under 10PSI. Idled around for another 30 min or so (1 hour total idle time including hose time) and pressure stayed at 7PSI idling around kicked in gear. Ran up to 3000RPM's for the next hour and pressure stayed around 10PSI. Varied the Rpms during that hour. For the next 2 hours up to 4000RPM's and pressure stayed around 12-14. No buzzer sounding off.
Going into the 5th hour ran up to 6000RPM's for a minute or two a couple of times and pressure went up to 25-26PSI. I'm not sure of the prop shaft height but i know I was under the pad with the sporty.

Does any of that sound OK?
Thanks
Craig
Hope to have a new temp sensor soon. I feel lost without a temp gauge working.

 

[Allyfishing]

i glad to here you are going to the lake a hose just don't work for me when i tune or or fire up a new rebuild i allways go to the big water just back it in and leave it hook up let the lower be under water leave the top off fire it up let it warm up wack it a a little and check the head temp make sure that the temp sensor in all the way in the head it's got to be against the head and make sure the end of the sensor is clean and inside the head

I should take a picture of the temp sensor that is on the engine now. When I pulled it out it is only a small metal cylinder with a plastic tube around it and held in place with a "Y" piece of metal that is secured by a small screw and the ground wire. I know it is too small to go all the way into the cavity on the port head. Does that sound right? Does anyone have a pic of one?

Thanks for helping me out with ideas here
Craig :beer:

 

[bruce pitts]

i gald that things went well on the sensor that what it is a round cylinder with a plastic tube that looks like a round wedge before you put the new one in clean the bottom of the hole good i use carb cleaner put the sensor in it will go all the way then put the plastic tube in istall the Y the water pressure looks good if the water temp is still cool at the lake u go to the temp should come up to 120 to 130 when the water warm it will come some here at home the lake water is still around 58 225 -260 -280 run 120 to130
look like the poppet valve is ok be safe and keep the dry side up

 

[Allyfishing]

See if I got this right...insert the metal sensor all the way into the hole til it bottoms out and then put the plastic sleeve in on top of it to hold it in? That's not how I pulled it out. The plastic sleeve was wrapped around the metal cylinder and inserted just inside the hole.

I'm not sure I understand this statement though, sorry:

"when the water warm it will come some here at home the lake water is still around 58 225 -260 -280 run 120 to130
look like the poppet valve is ok be safe and keep the dry side up"

I appreciate your help Bruce and sorry for not completely understanding. I am a newbie mechanic. But I do want to learn!
Thanks
Craig

 

[bruce pitts]

when you put the plastic sleeve it will slide down around the senser the plastic sleeve and the Y is what holds it in place if the one that was it was not all the way in and against the head it want work i have a repair book for a 225 promax here's my email bruce.pitts@kbr.com send me a address and i'll send it to you i have two it's good to have one it will help you a lot if want to learn about a promax it is a good all around engine a lot of things you can do to it make hp a fun engine

 

[Allyfishing]

I have the temp sensor and a new poppet valve kit ordered and will install then water test. If that does not solve the problem of the 30* difference in head temps and bring down the 26PSI at 6000RPM's then I will remove the divider plate and head gaskets to look for obstructions. I guess the last resort would be to lift the powerhead and check the divider plate gaskets??

Another question...is there a reason why the coolant lines from the port to starboard head thermostats covers are "T" so close to the port head? Any reason why they can't be "T" in the center and then run down to the mid and pee hole??
Thanks for the help
Craig :big grin

 

[bruce pitts]

how 's it going the repair book that on it's way to you will show you the water flow i make the pages for you did you get the tracking # i sent you

 

[Allyfishing]

No, I never got a tracking number. You sent it in an email? Maybe it went to spam and I deleted it by accident.
Thanks
Craig

 

[bruce pitts]

it will be there tuesday when i get home tonight i send it to you again

 

[XSive]

Craig have you called Tooter about this to either a) fix it or b) tell you what you actually have.

 

[Allyfishing]

Yes, we have been going thru the process of trouble shooting this. He's doing what he can for me on the phone but he feels bad being so far away. We are both puzzled. I sent ya a PM.

 

[Allyfishing]

Got it today Bruce!! Thanks a bunch! Good details and explanations. One step at a time now.
Thanks again
Craig:beer:

 

[bruce pitts]

i sent you a pm send me your email i have some i want to send you bruce.pitts@kbr.com