Another Mercury cooling question..

[Merc 2.5]

diverters will help in any block, any adapter combination.. merc started makin' .em standard in tha pro max (maybe '96/'97?) for that reason.. jus something i recently learned.. i ran them in everything i built back when..... 2.4's/xr4/xr6/2.5 steel/2.5 nic, one piece, two piece, stats, no stats, washers, poppet, no poppet... any comb. you can think of... didn't mater............ jmo.

So use washers and play with hole size til desired temp?

[tlwjkw]

hard ta judge ona computer??? for me anyway

[bayman96]

Baker343 & Merc 2.5,
Just thought that putting diverters in would help even the heat transfer around cylinders.That's the only reason why I put them in when I had the heads off. AM I mistaken?
But it kinda makes sense that they necessarily arent needed if using t-stats & poppet. Maybe they are creating just enough resistance (ie: pressure) and the poppet is dumping to soon?


PanRonnie,
I have the hose from bleed off on top of block down to poppet hooked up. Intrestingly enough when we plugged that hose off it actually got colder. This was just for trial and error and I plumbed it back to top of block. So I don't see an advantage putting a ball valve in line with that hose. Now if it would help with the poppet dumping down into the mid then yes I think that would work. Unless my thiniking is completly screwed up But thanks for the sugestion.

Bayman96 & Merc 2.5,
Intresting statment about installing restrictors insted of t-stats & that should increase my temps. Sounds like you'er forgetting Im taking temp reading with a wet sender & not off of head temp sender. Head temp makes more sense with your statment but than again I'm easily confused at this point. I know thats how they run with a one piece adaptor or if dry stacked but I'd really prefer not to go this route unless it's my last option. My limitor is set to 7000 R's & I dont plan on hitting it very offten.
By increasing volocity & decreasing the heat transfer, I would think I'd be reading even more cooler temps with a wet gauge. I'm also going to put my dump hoses back to factory routing again. Starbord side to port side then tee & run one out bottom of cowl & other into adaptor. I had it this way but with all the jacking around the other day I switched it so they both would dump out the bottom of the cowl.


FUJIMO,
Thanks for the explanation on the parts number thing. Good to know for future use.

Kirchner,
That is correct. Diverters should be installed 1/4" short below and on top.

As of right now my thoughts are maybe its just best to pull the heads and take the diverters out. If that dosent work then I'll try pulling the poppet, install a diffrent poppet cover, run restricted dump hose off that & dump off water with 1/8" hole in the washers where thermostats go. Only thing with that is I'm not sure if I'll have to fill in the one dump hole in the adaptor plate with epoxy in order for that to work?
I'll update with my findings after testing.
Thanks again for everyones help.

I see what you mean about a wet sender now, with the motor running can you hold your hand on the top of the cylinders? It can get tricky like that. But now that you say it, is your gauge correct fot that sender? the temp reading will be off if the gauge is for a head temp sensor

[tlwjkw]

think he says he's got an ir temp gun for comparison also..............

[A-train-97]

Yes, been feeling this old girl up with my hands a lot.
Seriously though yes I can keep my hand on outside of heads as long as I want. Top,middle, bottom it don’t matter all locations seemed nuke warm. At first in driveway on the hose different story.
Correct,verifying temps with handheld temp gun.
Water temp sender purchased new from Pro Marine. Part# 1941. I’m assuming it’s correct because when on hose in driveway (when I was able to get the stats to open)temps on gauge correlated with temp gun by +-10Deg.
Well it’s been driving me crazy the last couple of days so I pulled the diverters out last night. Going to go test it on the river right now. See what happens & update later today.

[PanRonnie]

I will be closing the base plate up to have it functioning similarly to the xs plate
Both my engines are mounted on 1 piece plates
Mount a bigger adapter on the poppet cover plate
Instead of water coming in it will flow water coming out of the poppet
T in a hose from the top of the block with a valve
So bleed off water will be dumped through this hose
The poppet with either the stock or xs spring

[A-train-97]

Diverters in or out today didn't make a split bit of diffrence so that answeres that.

Pletny of info shaired over the years for cooling mods & some of them i think would be salutions the simptoms & not to my core problem. I'm sure some of those salutions are necessary when running hard & probably have worked for many but I'm sticking with the stock t-satats and poppet should work best

for keep correct temps when turrning under 7k.


I think this post is definatly something I should look into cuz motor seems supper fat right now to me & idle quality seems all over the place sometimes so this makes good sense. If head temp switch is not working propely it will run 40% rich! Hmm this might be a problem.

[tlwjkw]

ya might be leanin' in tha right direction with those thoughts.............. good luck

jus curious.. what ecu?

[PanRonnie]

I would surely hope that there is an upper rpm limit for cold start enrichment
If you would operate the engine in extreem cold weather it would fall back in enrichment
Most aftermarket ecu's have this option

[A-train-97]

A26 box on right now that Brucato had checked & said all is good. Have new Brucato box on shelf but wasn’t gonna throw that on until after break in. Also have a A11 box on shelf that I haven’t tried yet. Not sure if all is good with the A11. I picked it up fairly cheep & there might be a reason.

[A-train-97]

I would surely hope that there is an upper rpm limit for cold start enrichment
If you would operate the engine in extreem cold weather it would fall back in enrichment
Most aftermarket ecu's have this option

Good point. Wonder if ECU will go 40% rich if temp sensor is faulty in any or all range of Operation?
Guess I got some more digging to do on here to see if this has been covered before. Thx

[PanRonnie]

Do you have the vst tank installed?
A newer ecu on an older vst tank would run richer

[PanRonnie]

I will be closing the base plate up to have it functioning similarly to the xs plate
Both my engines are mounted on 1 piece plates
Mount a bigger adapter on the poppet cover plate
Instead of water coming in it will flow water coming out of the poppet
T in a hose from the top of the block with a valve
So bleed off water will be dumped through this hose
The poppet with either the stock or xs spring

well finally time to put it back in one piece
the ProMax 225 poppet spring is stiffer than the 200XS spring
the promax spring is 1.6 mm
the 200XS spring is 1.4 mm