1989 Mariner 175Ski

[tlwjkw]

you need ta look at tha head and tha deck surface.. you will need a good/accurate straight edge... we have reused head gaskets (ones that were never over heated) many times over tha years without a problem... tha o-rings, not so much...

but at tha same time we mostly used regular heads and gaskets on our motors (had ta deck tha blocks 'bout 40 thousands also) that originally had o-rings.. was to expensive to cut tha o-ring head ta get tha compressiopn we were lookin' for back then...

[skialot2]

jus where in tha hell did you come up with this??? in your dreams??.. tha 2.0, 2.4, 2.5 has NEVER had a stat there............. not even for practice....

jan... tha few we had come thru tha shop "with that hole" and completely stock did not have any coolin' problems.. they were there for other reasons.........

I heard that it is the original thermostat location from Jerry Hale. RCKID74 on this site. He was the project engineer for Mercury's (Black Max) 2 liter V6. You can read all about it on this site. It is in a sticky in "Outboard and Racing history" called "Merc V6 History" started by warrior74z in 2007. It's somewhere around 15-20 pages in. It's one of the best reads on this site. Lots of cool information.

[tlwjkw]

if they in fact did it never went into production............. tha very first 1976 175 2.0 V6 on tha market had stats in tha heads................

one thing 'bout tha 175"ski" is thats its built from tha only steel sleeve 2.4 motor (XR4 rotating assy and only with tha mariner badge) merc built.. it seems like it (steel sleeve 2.4) was just an experiment that used tha public for their R and D...... jmo.

[tlwjkw]

jus another note.. that "extra hole" seem ta appear at tha same time they realized they had a coolin' problem with tha water cooled rec/reg... they may have been lookin' for any way possible ta help with its (rec/reg) problem... jmo

[skialot2]

if they in fact did it never went into production............. tha very first 1976 175 2.0 V6 on tha market had stats in tha heads................

one thing 'bout tha 175"ski" is thats its built from tha only steel sleeve 2.4 motor (XR4 rotating assy and only with tha mariner badge) merc built.. it seems like it (steel sleeve 2.4) was just an experiment that used tha public for their D and D...... jmo.

That is exactly correct. They never went to production with the stat next to the poppet. That is why the thermostats in the heads look like an afterthought with the hoses. They were.

[tlwjkw]

jus that something doesn't add up with that hole (which seems synonymous with tha XR4 block), 2 and 4 bolt poppets.. everything had a two bolt with first gen blocks.. then came a 4 bolt for a time then back to two bolt and then tha 4 bolt again.. i know why tha 4 bolt with tha hose goin' to tha top of tha block came about (and has stayed around tha longest) and what its for but don't have a clue as to why tha other changes were made.... jus never questioned it... they either worked or they didn't.. if they didn't, replace with what ever it called for... jmo.

[Glastron1987]

Would putting a little antisieze on the head gasket be a no-no so that it comes off easier and keep in in better shape for reuse?

[tlwjkw]

dry.. justa a touch of 2 stroke oil on tha bolt threads..... did ya check tha surfaces for being flat?

[skialot2]

everything had a two bolt with first gen blocks..

I have a 1st gen. 1976 175 Mercury serial #4303839 It has a 4 bolt poppet with the hose barb. I guess could it have been changed.

[skialot2]

jus that something doesn't add up with that hole (which seems synonymous with tha XR4 block), 2 and 4 bolt poppets.. everything had a two bolt with first gen blocks.. then came a 4 bolt for a time then back to two bolt and then tha 4 bolt again.. i know why tha 4 bolt with tha hose goin' to tha top of tha block came about (and has stayed around tha longest) and what its for but don't have a clue as to why tha other changes were made.... jus never questioned it... they either worked or they didn't.. if they didn't, replace with what ever it called for... jmo.

Actually, I looked it up. according to the schematics the original 2.0L V175 first poppet design was a 4-bolt design. Part # 68729(#3) It has the hole for a nipple, but it is not shown. Probably uses a plug.

The second poppet design was a 2-bolt design. Part # 66563A1(#6) No hole for barb

The 3rd design went back to a 4-bolt design. Part # 14462A1(#17) Comes from the factory with the hose nipple.

[tlwjkw]

had it backwards but i'm old and no books ta read... so glad ya got all that straightened out.. some had a nipple and some didn't.. no mater what merc wasn't consistent with a "single" poppet design that would probably work in any of tha V6 blocks.. its like they were just experimenting with 'em.. but merc was famous for **** such as that back then...... even more so in tha hi perf. division............. jmo

still think tha reason for extra small hole is in some way connected to tha 40 amp rec/reg coolin' problems.. they were gettin' air pockets (normal) in tha system that caused tha problems with it... seems ta be thats when it showed up...........

[pcrussell50]

still think tha reason for extra small hole is in some way connected to tha 40 amp rec/reg coolin' problems.. they were gettin' air pockets (normal) in tha system that caused tha problems with it... seems ta be thats when it showed up...........

This^^^

I’m sooo glad my 1990 2.4/200 was converted by the previous owner to 16A/clamshell cowl. It does still have the extra hose from the small side of the 4-bolt poppet, up to the top. But no water cooled regulators.

-Peter

[Aaronhl]

exhaust in the pee hole or steam??

I wouldnt put anti seize anywhere near a head at risk of getting in the head bolt holes and i have found that to be a problem finding correct torque...

[pcrussell50]

exhaust in the pee hole or steam??

I wouldnt put anti seize anywhere near a head at risk of getting in the head bolt holes and i have found that to be a problem finding correct torque...

This is legit.

The purpose of torquing correctly is to get the specified preload on the head bolt. If you are torquing with unspecified lubricants or bolts not specified in the manual, you are then guessing on the preload.

That said, on my 2.4/200 I used anti-seize on the head bolts. I check it frequently for loosening. I understand that I have no way to know if it’s over torqued.

-Peter

[Glastron1987]

Took the head off again, and I saw no sign of water breach, and the head and block look flat. I seriously think there is some other issue causing such a severe loss of water pressure.