4.3 l v6 mercruser head bolt torque specs

reptileguy

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Hey guys I have I believe is a 1989 4.3 litre v6 GM block and can't find head bolt specs anywhere for the engine. The only engine number I found.......oD489396..... On plastic cover on carb engine model is MCM 4.3 litre and displacement is 262 can anyone help me out with head bolt and intake manifold torque specs. Thank you
 

achris

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Head bolts - 75lb-ft (in stages)
Manifold bolts - 40lb-ft

Chris.....
 

reptileguy

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Thank you , on final torque stage do I need to warm up then cool engine before last torque
 

reptileguy

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Ok, the exhaust manifold I've been told 25ft lb but that seems low, as well the risers . Thanks everyone
 

Volphin

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I wouldn't put 40 on the intake.… Manual 7 states 30 ft-lbs for 12-bolt NON Vortec intake. If the intake was a 8 bolt vortec, the final torque is 11 ft-lbs.
 
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Fun Times

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I wouldn't put 40 on the intake.? Manual 7 states 30 ft-lbs for 12-bolt NON Vortec intake. If the intake was a 8 bolt vortec, the final torque is 11 ft-lbs.
Any chance of posting what you're seeing inside service manual #7?

For the year in question (89) everything seems to read 40 with nothing revised in any of the V6's service literature that I could find until the next service manual # 18 which did drop the torque to 35 ft pounds which incidentally I just re-noticed became 4.3l/LX Gen 2 in 1991.
http://www.boatfix.com/merc/Bullet/85/85_21.pdf
http://www.boatfix.com/merc/Bullet/91/91_17.pdf
http://www.boatinfo.no/lib/mercruise...ser7.html#/152
http://www.boatinfo.no/lib/mercruise...ser18.html#/42

While were confirming the torque settings, may as well add that the older 185 (4 BBL.) GM 229 V-6 1983-1984 shows 30 ft.-lbs. http://www.boatfix.com/merc/Bullet/83/83_09.pdf

And the Gen+ is 11 fl-lbs. http://www.boatfix.com/merc/Bullet/97/97_01.pdf

In the end of it all torqueing to 35 or 40 should do the job just fine on the 89 engine models.
 

reptileguy

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I put it to 30 and seems not very tight I'm going to go to 35 lol any ways what should exhaust manifolds be
 

Volphin

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Any chance of posting what you're seeing inside service manual #7?

For the year in question (89) everything seems to read 40 with nothing revised in any of the V6's service literature that I could find until the next service manual # 18 which did drop the torque to 35 ft pounds which incidentally I just re-noticed became 4.3l/LX Gen 2 in 1991.
http://www.boatfix.com/merc/Bullet/85/85_21.pdf
http://www.boatfix.com/merc/Bullet/91/91_17.pdf
http://www.boatinfo.no/lib/mercruise...ser7.html#/152
http://www.boatinfo.no/lib/mercruise...ser18.html#/42

While were confirming the torque settings, may as well add that the older 185 (4 BBL.) GM 229 V-6 1983-1984 shows 30 ft.-lbs. http://www.boatfix.com/merc/Bullet/83/83_09.pdf

And the Gen+ is 11 fl-lbs. http://www.boatfix.com/merc/Bullet/97/97_01.pdf

In the end of it all torqueing to 35 or 40 should do the job just fine on the 89 engine models.

Here ya go? p.98 of the pdf if ya have it. If using the hardcover, it is in section 3A, Page 1.
HTH
 

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Fun Times

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Thanks, I don't have one.

Looks like they did a few reversions of this manual and at one point they did have a bulletin come out about the (TORSIONAL (CRANKSHAFT) DAMPER BOLT TORQUE CHANGE) so both you guys need to be careful about that, service bulletin - Boat Parts, Marine Engine Parts, Boat ...

Notice the end of the part number sequence is a little different between the manuals such as your 2-190 is separated unlike the boat info manual. Also here is another one that ends in 2-1293, http://www.ebay.ph/itm/1994-Mercrui...ines-GM-V-6-P-N-90-12410-2-1293-/281714576528
And there seem to be a few other different ending numbers as well.http://www.ebay.ph/sch/i.html?_odkw...R40&_trksid=m570.l1313&_nkw=90-12410&_sacat=0

There's just a misprint somewhere along the line.
 

achris

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Here ya go? p.98 of the pdf if ya have it. If using the hardcover, it is in section 3A, Page 1.
HTH

Section 3A is for the 229 V6, not the 262 V6. Section 3B is what you want for the 262.... Here's the RIGHT page.... (and it states: Intake Manifold - 40lb-ft)

 
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