HARRISONMIRAGE

Those IR guns don't read right on the brass fittings.The readings will vary with the color of material you shoot it at.There is a fancy word for the theory behind it that an engineering bud of mine told me.If I remember ill let you know.

blue thunder

Its called "emissivity" Harrison. Fancy IR guns have a pot to adjust for emissivity.

BT

Mr Gadgets

Believe me I didnt trust it, but after several times looking at things, I think I eliminated the emissivity problem, to some degree. Shooting at the same type and style of fittings should have gotten me close. I have bypassed the tstat and will now wait for the new cam and then go test again.. Gotta love this boating thing!!

Thanks
Dick

ActiveFun

I have been having a oil temp problem for a while and it is totally resolved. For a couple of years I was running approx 190* oil temp and last year it went way up so I replaced the oil cooler with a new mercruiser 800 hp cooler. It wasn't the problem. After a rebuild this winter the oil temp was reading very high, up to 260 + and without beating on the motor. I turns out their are check valves in the motor which in case of a clogged filter it allows oil to flow to the motor and by-pass the filter/cooler area. We closed up the check valves and the problem is totally solved. I cant get the engine hot if I keep the throttle open for hours.

Mr Gadgets

I am running a Merlin super tall deck block and I can remember what valving is included, but I always plumb it so all the oil is forced through the filter/cooler, so that shouldnt be an issue. But it is a very good point.
Thanks
Dick

Mr Gadgets

Well here is an update to my situation.
I got a chance to run the boat yesterday. I was in the process of tuning the EFI and only made one pass on the river at wot. I did make three or four passes as i was tuning and worked my way up to wot. The Cutler EFI is self tuning and that is the process. Anyway. I saw oil temp at 180 after the second pass. I was up to about 4k rpm at that point. The next pass was worked up to 5400rpm at wot and the temp went to 220*. In the past I have done the same tuning procedure and saw 250* after the same amount of runs.
I ran on the Big lake and it never went over 225*, but I was unable to run over about 4600, but I did that for a 12.5 mile run. So I am leaning toward the KE Oil stat being the problem. I believe it was not forcing all the oil thru the cooler, only part of it. Not sure why, but I mean to investigate. I paid good money for that stat and want an answer.. I will keep you posted..

Dick

Lmarth

Blue Thunder is right on if my feeble mind is still working. I believe the color Black has the highest rate of emissivity.

cooltoys61

Just wondering why you think a rebuild or cam is ness. because you lash is off on one valve. Could be the lobe but I'd check the lift there to be sure before I tore it down,could be it just backed off the nut a little. I'm sure you knew this though.
Also I've always read to paint manifolds, etc, that you want to disperse heat ,black. Assuming, of course, it's out of the sun. Any truth to this and maybe related to the emissivity? Sorta like the little toy I got at the space center as a kid that spun the vanes when placed in the sun because they are black on one side white on the other?.

MACDAD260

Glad to see you're making progress on the oil temp, Dick. I run a Perma-Cool T-stat and I sometimes question it's value although, I do believe that when the oil warms up all of it is going through the cooler. It's just that when the oil is cold it still allows some oil to go through the cooler, too. Does Merc use a T-stat on the HP motors? If they do where is it located and why don't we all just run those? They seem to work. I am all for letting someone else work out the kinks and then steal their ideas.

Mr Gadgets

Cooltoys,
Check my post on Pot holes in cam lobes.. that will explain what I found. I did replace the cam and set it all back up. Ran the snot out of it on Sunday and my oil temps have not gone over the 225* mark. Well the gauge is not very well graduated, but the needle goes a bit over the 220* mark. I am liking what I see at this point. It still takes a while for the oil to get to temp, but it did that even with the stat in place, so it just plain wasnt functioning. Theroy was good, but in my case, practical application was not good. I want to know why. I spent hard earned money on that thing. But for now I am boating and that is what counts. I will be working on a different way to not cool the oil until it gets to temp. But too many irons in the fire at this moment.

Macdad, I am not sure what else is out there. In the begining of the boat rigging, I did my research and thought I was all set with the KE part. I will look at other stuff, when the cold weather hits, but for now, I am a happy camper. I ran from Muskegon to GH most of th way at speed yesterday. Even managed a best of 76mph in the slop. And like I said, I havent seen over 225*. I need some flatter water so I can make the whole 12mi run at 5000rpm to really test the system.

Like my buddy said... problem solved!
Thanks for everyone's input.
Dick