Seirra gaskets

[GLEN HARRIER]

I have been through two head gaskets made by seirra. does anyone know where I can get A metal one? That is what come off it. An the one's I get keep blowing . An they have been installed right. The head an block have been machined . By the way the engine is a 3.0 model # 302amkw Can I get a auto gasket that will interchange, probably a stupid question, sorry.

 

[HT32BSX115]

Re: Seirra gaskets

Howdy,

Not a stupid question at all!

It should not matter who's head gasket you're installing (assuming it's the right one)

Do you have a cracked block that has been "repaired"?

 

[GLEN HARRIER]

Re: Seirra gaskets

No sir. Boat runs great for about one day . Never had this problem with the metal gasket. Did not blow the metal one. Re-ringed the motor. Is when the problem started.

 

[Reinell-BRXL-191]

Re: Seirra gaskets

there is an original OMC one on eBay right now - Good price - your engine comes out to be a 1986 - this is from a 1990's model - but the sierra number says that it replaced both your part number and this part number - and by looking at them, they should be the same

http://www.ebay.com/itm/OMC-Cylinde..._Accessories_Gear&hash=item519fc74819&vxp=mtr

 

[GLEN HARRIER]

Re: Seirra gaskets

Thanks alot . Happy boating.

 

[Reinell-BRXL-191]

Re: Seirra gaskets

Just in case you are worried it's not the same one - here is the sierra info ( they are the same gasket )

Replaces OEM
Chris Craft 16.50-00204
Mercury Marine 27-52364
OMC 3853336
OMC 908611 - This is your part number
OMC 913274
OMC 914812 - This is the part number of the link I sent you
Volvo 3853336
Volvo 908611
Volvo 3853336

 

[HT32BSX115]

Re: Seirra gaskets

Well, since there's literally hundreds of thousands of engines out there in radio land with "composite" head gaskets that don't fail, it's unlikely your problem is the head gasket material.

Maybe you have a bad "deck", bad (stripped/pulled) headbolt(s), way high compression, etc.

Also, a detonation event can easily "blow" a head gasket.

How much did you take off the deck and head? Did you check the compression after you put it together?

 

[bruceb58]

Re: Seirra gaskets

Are you tightening the head bolts in the proper sequence using a torque wrench.

May be a silly question but still have to ask it.

 

[Reinell-BRXL-191]

Re: Seirra gaskets

Did the head gaskets blow in the same place? If so, I would take a straight edge to the head and block and make sure your machinist didn't hose something up.. You may also have some stretched head bolts, I would consider replacing them if your not sure. I would also run a tap thru all of the block threads, and as suggested, make sure to torque it down in the proper sequence and to the suggested ft/lbs with a known good torque wrench.

Knowing where the head gasket is failing, would help diagnose the cause of the failure...

 

[GLEN HARRIER]

Re: Seirra gaskets

My be thats it. Can you tell me what the proper sequence is. WILL SEE IF MY MECHANIC KNOWS WHAT HE IS DOING !!! I KNOW HE IS TORQUING AT 100 LBS.

 

[Reinell-BRXL-191]

Re: Seirra gaskets

Here is the sequence, make sure the bolts are not torque to yield, as I mentioned before, a stretched head bolt will pop a gasket every time.. look at the threads as shown in the diagram.

Also, if your mechanic is old school, make sure he is not coating the composite gaskets with anything.. only steel gaskets get coated... and of course, don't tighten each bolt to final torque all at once, go slowly in this sequence until your final 90-100 lbs is reached

 

[bruceb58]

Re: Seirra gaskets

100lbs is correct.