omc thermostat housing

[drem312]

1989 rebuilt gm motor 5.7 omc stuff on it,, my engine seemd to be running hot the guage would stay around 160 then when under power jump to 200-210 I back it down then it cool quickly so I removed the risers and manifolds split them apart and cleaned them out I then removed the thermostat housing and noticed that there was a 54 mm 195 round car engine looking thermostat right on the intake but the where the originally thermostat is suppose to go up in the housing is gone and its all rusty it looks as if someone bypassed it looking at the water flow in my manual it seems that this type of set up would work,,so I bought another thermostat ended up being a mercruiser sierra part 160 degree on but now it doesnt even get up to 120-130 ... I do not have a heat gun to test it at the engine to see and I will test the temp guage tonight but could this set up with the thermostat in the intake work or should I buy a thermo housing and Omc 160 thermostat... the thermo housing seems to have the thermostat suspend above the
1 1/4 hole in the intake where the housing connects or is there something missing in there too it seems that it the oring holding the thermostat in the housing should fail it could fall right into the intake manifold any thoughts thanks


up date so tonight i removed the housing and figured out why the engine wasnt warming the thermo I put it was sideways in the intake I guess the housing doesnt hold it down securely so If i buy a new housing and use the original 160 small thermo that goes up inside is there something else I need for the intake? or is this how the set up is the big opening in the intake sorry anout the steering wheel pic that is a light that came on trying to figure if its a light that comes on when the key is on or if its an alarm of somesort

 

[drem312]

Re: omc thermostat housing

Anyone have pics of the inside of an Omc thermostat housing besides the thermostat OS there any this else that goes up there? Anything else that sits on top of manifold ?

 

[Howard Sterndrive]

Re: omc thermostat housing

I don't have pics, but the stat just fits up in the top of the housing, spring down, and a fairly meaty oring goes in the recess to hold it up in there. shop.evinrude.com has all the exploded views.

 

[drem312]

Re: omc thermostat housing

thank you,,, and the intake manifold that just has the hole the thermo housing sits over nothing else there?

 

[Howard Sterndrive]

Re: omc thermostat housing

nothing else

and remember the spring faces down on the thermostat
you can use a seal pick or small thin screwdriver to work the oring into the groove to hold it up there

 

[drem312]

Re: omc thermostat housing

ok looks like Im buying a new housing and thermostat,,I just bought the other one you think that set upo would work if i can find a way like a thicker gasket to hold the 54 mm thermostat to the intake?

 

[Howard Sterndrive]

Re: omc thermostat housing

I can't see anything of value in your pics of the housing - are you saying it's the wrong one on there? or it rotted?

a few on ebay in the $40 - $50 range
$85 at the dealer brand new - hardly worth going used.

 

[Lou C]

Re: omc thermostat housing

As Howard said, the OE thermostat on an OMC or newer Volvo for the V8 and V6 engines are held into the thermo housing, not the intake, with a rubber ring that fits into a groove in the thermo housing, the spring goes down, but you really can't put it in backwards and have it all fit together. O-ring is part #52, thermo is part#56. You may be able to re-use that housing if it's not too rusted, you may have to soak the inside in PB Blaster and scrape the rust out of the groove, but make sure the water passages to the manifolds are not necked down with rust. I replaced my old housing in 2003 (salt water use) and it's still fine, the old one is still usable and I keep it on the boat with a good thermo already installed so I can replace it on the water if needed....

http://www.dougrussell.com/partscat...6,688,687,689,690,691,692,693,694,695,696,697

 

[drem312]

Re: omc thermostat housing

Im gonna try and get just the new thermostat and see if I can get that ring to fit in after i clean the inside up ,,I understand now the way it is suppose to go back together my second question was the way the jimmy rigged it with a thermostat in the intake I was wondering if that set up would work b/c I did just buy a 25 dollar 160 degree one the problem is the housing doesnt hold that style down to the intake I would have to fabricate a metal gasket to keep it in place or a thicker gasket with some permantex..,,,, didnt know if that waould cause flow problems,,

 

[Howard Sterndrive]

Re: omc thermostat housing

A lot of engineering went in to the division of flow between the block, and the manifolds.... don't mess with it to save the cost of 5 minutes worth of gas

you'll never have peace of mind blasting down the lake if you try to reinvent the wheel. you'll be staring at that needle the whole ride.

 

[drem312]

Re: omc thermostat housing

I agree I dont think I can save the housing so I just ordered the housing and a 143 dgree thermostat from Ebasicpower thanks for the help

 

[drem312]

Re: omc thermostat housing

Finally got the new stuff in and my question is once I put the thermostat in followed by the o ring it seems the o ring doesn't fit right I pushed it in the groove but of I wiggle the thermostat and pull up the thermostat. and o ring pull out. I really don't want this thermostat and o ring to fall into the intake then block a passage on the head any ideas

 

[Howard Sterndrive]

Re: omc thermostat housing

sounds like you got some mismatched parts.. I can't pull my thermostat out past the oring. I can rotate it, but not pull it out.

is there a 143 degree OMC thermostat?
I thought 160 was the lowest...
I suspect you have a mercruiser 143 thermostat and that's why it doesn't fit

I'm guessing, but pretty sure there's no 143 OMC stat because my Mercruiser engine runs an OMC thermostat housing (mongrel boat) and I ended up cutting a coil off the 160 thermostat spring to make it a 150. If there was a 143 I would have just ordered that.
I was surprised how easy and effective cutting 1 coil off was, btw.

 

[drem312]

Re: omc thermostat housing

Ebasic power has a 143 thermostat. That's for a Omc v8 motor and I matched the housing

 

[Howard Sterndrive]

Re: omc thermostat housing

what's the part number of the thermostat you ordered from Ebasic?

if you bought everything there and it's supposed to all fit together, phone Ebasic Power..they obviously screwed something up.

I don't think there's a 143 OMC stat...
0383307 THERMOSTAT is the correct part for your motor and it's a 160

 

[sethjon]

Re: omc thermostat housing

View attachment 101380View attachment 101382View attachment 1013791989 rebuilt gm motor 5.7 omc stuff on it,, my engine seemd to be running hot the guage would stay around 160 then when under power jump to 200-210 I back it down then it cool quickly so I removed the risers and manifolds split them apart and cleaned them out I then removed the thermostat housing and noticed that there was a 54 mm 195 round car engine looking thermostat right on the intake but the where the originally thermostat is suppose to go up in the housing is gone and its all rusty it looks as if someone bypassed it looking at the water flow in my manual it seems that this type of set up would work,,so I bought another thermostat ended up being a mercruiser sierra part 160 degree on but now it doesnt even get up to 120-130 ... I do not have a heat gun to test it at the engine to see and I will test the temp guage tonight but could this set up with the thermostat in the intake work or should I buy a thermo housing and Omc 160 thermostat... the thermo housing seems to have the thermostat suspend above the
1 1/4 hole in the intake where the housing connects or is there something missing in there too it seems that it the oring holding the thermostat in the housing should fail it could fall right into the intake manifold any thoughts thanks


up date so tonight i removed the housing and figured out why the engine wasnt warming the thermo I put it was sideways in the intake I guess the housing doesnt hold it down securely so If i buy a new housing and use the original 160 small thermo that goes up inside is there something else I need for the intake? or is this how the set up is the big opening in the intake sorry anout the steering wheel pic that is a light that came on trying to figure if its a light that comes on when the key is on or if its an alarm of somesort

Its damn hard to read without periods!

 

[drem312]

Re: omc thermostat housing

The part number from Ebasic is GLM13431 and I matched it with a new housing GLM22600.( < note period I added here) I will try and attatch a pic of what Im talking about . The 160 Thermostat is the same size as the 143. It seems to fit perfectly in there its the oring that really doesnt snap in there. maybe Im wrong but I think that with the hot and cold salt water it will un-snap itself and fall right into the intake

 

[drem312]

Re: omc thermostat housing

Just got off the phone with Ebasic Power those two parts match. I guess I have to stretch or get a new oring because I know this thing is not right ,

 

[Howard Sterndrive]

Re: omc thermostat housing

not an ebasic fan...no message board over there to ask for help. but iboats sells aftermarket too. can get OEM stuff at marineengine.com

the stat is probably fine, but I wouldn't trust that o-ring - mine fits a lot tighter than that..and rounder - try to get one a touch bigger

don't need name calling here. everyone's trying to read your post because they want to help you. it's hard to read without any punctuation.

 

[drem312]

Re: omc thermostat housing

I was able to heat and stretch it a little bigger (enough for it to snap in place), but Im going to try and get a bigger one like you said because when it gets cold it could shrink again thanks for all you help