Cylinder head question?

[andy6374]

My Engine: 88' V6 200Hp Black Max..<br /><br />Looking in my merc manual, it shows a cylinder head and a head cover. Each of which have a gasket. And I imagine the water jacket is under the head cover.<br /><br />But....<br />My engine was recently rebuilt (2004) and appears to have one peice cylinder heads. Is this correct or is my vision blurred. If they are one peice heads, where's the water jacket located.

 

[andy6374]

Re: Cylinder head question?

What is the advantage to one peice heads.

 

[andy6374]

Re: Cylinder head question?

bump.<br /><br />Just interested.

 

[rodbolt]

Re: Cylinder head question?

was your engine rebuilt or replaced? its a very easy thing. some heads had water jacket covers and later ones in the early 90's did not as they went to a different casting procedure and eliminated the cover.

 

[andy6374]

Re: Cylinder head question?

Rodbolt-<br />The mechanic said it was a rebuilt 88'. But everything tells me it is a different powerhead.<br /><br />Reasons:<br />1.) Obviously this one piece cylinder heads. <br />2.)On the port side cylinder head, under the # 2 spark plug I have two tan wires (one short, one long) the long one I use for temp gauge. I also have a tan/blk wire coming out coming out from the same place. On the starboard head I have a tan/blu which is the overheat sensor.<br />3.) The yellow/blk wire from the engine harness was tucked away (as if it was an efi). I had to dig it out to connect it to the enricher valve to get the push to choke to work. This in conjuction with the tan/blk wire on the port head is really confusing.<br />4.) But to confuse things, the serial number on the mounting bracket is 0b303415, ie an 88'. He could have used the old bracket and new powerhead. But I am not really sure.<br /><br />-andy

 

[rodbolt]

Re: Cylinder head question?

the mounting bracket has nothing to do with the powerhead<br /> keep looking for differences. not that it matters most the time, until you have to buy engine parts. then it may matter.

 

[andy6374]

Re: Cylinder head question?

Yeah I know the mounting bracket has nothing to do with the powerhead, I just mentioned because it added to the list of things that don't seem to add up (damm that's good vocabulary, add this add that).<br /><br />The differences I mentioned are the only ones. Oh well, the engine runs great. Just curious like I said.

 

[rodbolt]

Re: Cylinder head question?

let me hunt about a bit see what i can come up with

 

[gss036]

Re: Cylinder head question?

Andy, use this sr# OC198948 and look at Mercury Express parts and you will see the difference. You probably have an 89-90 powerhead, 2.4Liter engine.

 

[andy6374]

Re: Cylinder head question?

That's good to know. Yep that's my cylinder head, but everything also looks like mine 0b303415. How different are the 88' and the 89'. I couldn't view my cylinder head on merc parts express because it gave me a blank page when I clicked on cylinder head on merc parts express.<br /><br />I need to know for sure though because I want to replace my head gaskets over the winter. But via inspection they are definitely one piece heads.

 

[gss036]

Re: Cylinder head question?

I checked the part numbers listed for ob303415 and they are the same number for the head and the gasket set as the other number.

 

[andy6374]

Re: Cylinder head question?

Wierd, maybe my merc manual (published 1988, New Brunswick Corp.) isn't for my engine. I got the manual number from www.maxrules.com.<br /><br />The manual also only shows design I & II for the relief valve system, when mine is a design III.

 

[gss036]

Re: Cylinder head question?

Could be. The manual I have lists all the sr#'s covered in the manual. For the 200's it is 0C100861 thru 0C291519. I think they interchange the "O" & "0". It also covers 135-175's 0C100861-0C221499. Published in 1990 90-814098--1 190<br /><br />I went over that site and I cannot find you motor listed. Might be that it was a late run 1988 and they used the new 89 powerhead?? Maybe that is why you drew a blank document of Mercury Parts Express.<br />I did not see any 303 sr#'s until 1995-96 years and they were "G303,etc"<br />Possible some ingenious mechanic canablized more than one engine to come uo with what you have. The wrecking yards do that with auto all the time.

 

[andy6374]

Re: Cylinder head question?

Well, 200 hp 88's start with 0b241881 (according to www.maxrules.com).<br /><br />I always used to be able to view my outboard, 0b303415, on mercpartsexpress until a week or two ago. I think they are in the process of updating that website, you can tell the fonts are different. Mercpartexpress does label it as a 2.4L, which it is.

 

[andy6374]

Re: Cylinder head question?

Well I can finally view the diagrams of my engine on mercpartsexpress. They actually show both design, i.e., the 2 piece and 1 piece design cylinder heads. It is just funny that it is not in the manual.