High water pressure & low water temp

[22R]

I had a similar problem on my modded XR6 in 2011. maybe this thread will give you some insight or other ideas.
I wound up pulling my powerhead off and back blowing and running weed eater string through all openings and when I put it back on everything went back to normal. I do not have T'stats though. Hope yo get it figured out
http://forum.allisonowners.net/index...ressure.10621/

22R

[H20WKD]

22R,

Thanks for the link...

What I've done so far has gotten the WP down, but not perfect and still running too cool.

I have been studying the water flow charts for the 200xs and one thing I can't figure out....the small diameter side of the poppet has a brass plug in the cover, the casting hole in the engine block does not have a water passage in it for that side of the poppet????

On edit...

I've done quite a few poppet kit installs on the 2.5's over the years and always wondered about the white plastic washer that comes in the kit????


I have never seen it installed on any assembly I've taken out......BUT I did see a photo on the google with the diaphragm assembled like this......what think you??



Bob

[bigboy]

On my 2.5 200 the washer is installed.

Do you have a gen2 optimax? What temp and pressure was It running when All was good?

If i understand you right there is no water hose running from the top of the block to the poppet cover?

You have a 1 piece exhaust plate?

[H20WKD]

Yes... Gen2 200xs 2013.

The motor had 120hrs when we got it, pressure has always been high at idle.
I inspected the poppet, no white washer was installed. Installed the rebuild kit.

No water hose to the poppet cover. The hose on the top of the block goes to the air compressor intake, out let directly to the telltail.

Yes one piece exhaust plate.

Is there an open water passage behind the small end of the poppet cover?

[bigboy]

No passage on mine.

Did it run warmer when You first got it?

Can You compare water temp and psi with another 200xs owner?

[H20WKD]

I've got two members on the Ally Boards checking for me.

I didn't notice it right away, it may have been. I was pretty busy learning how to pilot the damn thing.
I doubt it though, I really only noticed it the first time I put it on the hose. The stats never opened, and my IR gun showed low cyl head temps, all-around 105-120*F.

I know for sure the white washer was not on my '04 225X PM.

[H20WKD]

Wit's end....got the idle water pressure,(more spring tension, installed the white washer), down to 4.6psi, 95-98*.
Stats still not opening.
Had an intermittent misfire, found a small gas leak on #5 cylinder, replaced split injector "O" ring.
Much better idle but still running cold......

Awaiting call back from Merc Perf.

Bob

[bigboy]

Strange that the idle water pressure is going down. At idle the poppet should be closed. Maybe this leaks a bit but by making the poppet spring stiffer it should just seal better and thus raise the idle pressure.

[H20WKD]

Well.... after following the flow chart in the manual, with the poppet closed the 'stats are supposed to regulate the temps.
A very small stream of water is getting by the relief slot in the stats, but water temp is too low to open them.
The discharge passage in the poppet is open. The running pressures are all within spec's, so I know it's opening properly.
I just don't understand how the running pressures can be ok and the temps under 95*. Lake temps 68*.

Bob

[bigboy]

I got a water flow chart of the 200xs (thanks Bob).

Seems like the 200xs has the block drains where the hi perf engines have them. The flow chart was with the 2 piece adapter. I wonder if any of the promax gurus here ran their engine with the block drains as the hi perf in conjunction with the 2 piece adapter?

Wondering if there was any noticable difference.

[H20WKD]

Well yesterday I ran with the exhaust snout completely open.....I previously had only three holes open.


Temps stayed above 110* at all times with no change in WP at idle, still 4-5psi, ??????

Bob

[bigboy]

So it's runner hotter with the exhaust snout open? Real strange? Hard to believe it is due to this.

You are talking about head temp right? Not water temp?

[H20WKD]

Yep...That was the only thing I changed before yesterdays outing. Same temps & pressures today.
Hope to get out a few more times this Season....the motor is running much better, BUT... I have nothing but a 2004 225x PM to compare it with. Mid range punch is much better than the PM, I'm still working on the hole shot.


MercMonitor....gauge 'sez, water temp, but both cylinder heads have a temp sensor, I believe connected to the ECM, to enable limp mode if things get too hot.

Bob

[Go Time]

Those temp senders in the oring heads measure water temp.

[checkmate45]

Ive got a similar issue of high water pressure but the motor runs hot, not cold. This is on a 1994 150hp promax 2.5L. New thermostats and have inspected the poppet valve 3 times over the course of 3 weeks. I have not found a thing wrong with the cooling system but the motor overheats. It was running hot before with my coned 200 case (around 170 degrees or higher depending on how long i cruised slow) and its worse with my 2 hole cle on it. It has tripped the overheat alarm with the 2 hole cle. Water pressure is between 20-25lbs with either lower unit. Im going to try a different w/p gauge this week. Any thoughts? Is it possible that something plugging a dump hole in the adaptor plate would cause overheating?