mercruiser 5.0 Tstat issues need help

[jws123]

Picked up a boat it has a merc 5.0 alpha 1 gen 2 in it couldn't figure out why engine wouldn't heat up found out NO tstat in it some idiot i guess took it out who ever owned it before me must of been a butch. The tstat housing was hollow. Now my problem is i went to go get a new one from boat store gave em engine number ect got home and the tstat didn't fit inside the housing like not even close...they said its the right one when i called them back but its not i cant find what one i need . any help would be appreciated

The number on my tstat housing mercruiser 16413-c
My engine serial number 0d704753
the tstat kit they gave me quick silver 807252q-5

 

[alldodge]

Which thermostat housing do you have, could be one of 3

 

[jws123]

Which thermostat housing do you have, could be one of 3

Looks like the 3rd one here is some pics you can see it doesnt fit to.

 

[crazy charlie]

What you have to do is pry out the retainer that looks like it is in place.It is either plastic or brass.Yours looks like the plastic style.Easily replaced if you have to break it to get it out.Then clean up the inside and edges with wire brush and flat screwdriver .Tstat will then sit down low and the retainer will then go in lining up with groove.When winterizing motor the tstat is commonly removed so the previous owner may not have been a hack ......or he l\may have been hiding a temp problem.Hope it is not the later.Charlie

 

[jws123]

What you have to do is pry out the retainer that looks like it is in place.It is either plastic or brass.Yours looks like the plastic style.Easily replaced if you have to break it to get it out.Then clean up the inside and edges with wire brush and flat screwdriver .Tstat will then sit down low and the retainer will then go in lining up with groove.When winterizing motor the tstat is commonly removed so the previous owner may not have been a hack ......or he l\may have been hiding a temp problem.Hope it is not the later.Charlie

thanks will make sure no sleeve is in there

 

[crazy charlie]

The retainer is there,i can see it.Look on the edges where you did some grinding,you will see a shiney metal,thats the retainer.Tap a small screwdriver doen on the bright shiney part and it will seperate.Had same so I am sure of it

 

[alldodge]

I'm sorry to say that according to Merc site and BAM, both list what you have as the replacement. Also see that the Stat will not fit in your housing. Main reason is once installed the plate cannot be bolted in place. It needs the Stat which sits down inside the housing

Need some Merc insight, hey Fun Times or muc have any insight?

Your housing doesn't look good, and the check balls are in pretty bad shape.

Edit: looks like Charlie has a better eye then me this evening

 

[jws123]

I'm sorry to say that according to Merc site and BAM, both list what you have as the replacement. Also see that the Stat will not fit in your housing. Main reason is once installed the plate cannot be bolted in place. It needs the Stat which sits down inside the housing

Need some Merc insight, hey Fun Times or muc have any insight?

Your housing doesn't look good, and the check balls are in pretty bad shape.

Edit: looks like Charlie has a better eye then me this evening

he has a better eye then both of us i didnt even see it and i looked 100 times lmaoo it looked like 1 solid peice going to try and cut or hammer it out and yea the boat sat for 8 years everything is crunchy just put new risers on ect.

 

[crazy charlie]

he has a better eye then both of us i didnt even see it and i looked 100 times lmaoo

My Dad was a marksmen,guess I inherited his eyesight!!lol

 

[jws123]

Yep that was the poroblem lol i feel stupid but least its done ty

 

[Fun Times]

Charlie has him heading in the right direction.

The 807252Q-5 is a 160 degree kit while 807252Q-4 is the 140 degree kit that is typically more common found/used unless you're in the Bodensee (Lake Constance) area as the 160 is more used to help lower emissions, etc...Plus if you plan to run in salt water type then the 140 would be the better choice too...Other than that 160 is okay to use...Just figured you'd like to know. OEM MERCRUISER THERMOSTAT STAT KIT GM 140 degree V6 V8 807252Q4


You may want to buy a new sleeve merc item number 10 / part number 23-806922 and don't forget to put your O-ring down first before the thermostat item number 7, https://www.mercruiserparts.com/bam/...31719/1014/220

Should look like the following photos, https://www.nlamarine.com/products/m...-v6-v8-305-350

Edit: ^, Looks like I'm late to the repair party.

 

[crazy charlie]

get the inside and rim cleaned up good so the new retainer goes in smoothly.

 

[jws123]

tstat is now in how 160f how ever i noticed when running it wants to hang around 175-180f but it wont go past that i let it run on hose for about 20 mins does that seam a little warm? my old boat would never go past 165

Also all new water pumps installed and new risers.

 

[crazy charlie]

yes a little too warm,especially since salt water crystalizes at 190.You are in salt?? The correct tsttat is 140 or 143

 

[jws123]

yes a little too warm,especially since salt water crystalizes at 190.You are in salt?? The correct tsttat is 140 or 143

yea salt water ima go swap it for a lower temp i think they told me 160 but appears this engine doesnt like that il keep the 160 for my other boat.

 

[crazy charlie]

I will keep my fingers crossed that the prev owner wasnt hiding an issue .Charlie

 

[jws123]

I will keep my fingers crossed that the prev owner wasnt hiding an issue .Charlie

hoping its just the tstat because it wont go past 180f no matter what so dropping to a 140f ordered it waiting for it to get here. water appeats to flow good out both ports no water in oil and it runs surprisingly good after sitting 8 years only 400 hours on it.

 

[crazy charlie]

Fingers crossed,post results

 

[jws123]

runs at 160f now much better with a 140tstat why the difference idk but hopefully once i take it out and blow the **** out of it will be lil better its been sitting for a long time i put new risers and flushed lines out but who knows whats built up int he block ect.

 

[alldodge]

The 160 is good for anyone in fresh water, 140 is for slat water because there is less erosion over time