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climbinggod
03-13-2008, 07:04 PM
Anyone know the torque specs for a Ford 351w HO Indmar engine. I had to undo the 2 bolts that hold the throttle cable bracket on.

Covi
03-13-2008, 07:27 PM
I am a huge fan of tightening per torque specs! I don't know the answer, but I'm sure it will be along shortly! Great question!

BrianM
03-13-2008, 07:31 PM
According to my Ford small block rebuilding book it should be 55 -65 ft lbs

climbinggod
03-13-2008, 08:30 PM
According to my Ford small block rebuilding book it should be 55 -65 ft lbs
Thanks Brian

Laurel_Lake_Skier
03-13-2008, 09:23 PM
Looking at my Indmar manual, the 55-65 is for the 302. 351 says to tighten in steps. First to 85 ft/lbs then a final to 95 ft/lbs. The 351 uses larger 1/2" bolts. Also, there is a tightening sequence, starting in the center and moving out.....not sure what effect pulling out one or two bolts will have on needing to follow the sequence.

JLeuck64
03-13-2008, 10:31 PM
I am thinking those 351's used INTAKE manifold bolts to hold the throttle cable bracket in place. If so, the specs for them would be a lot less than a cylinder head bolt...

climbinggod
03-13-2008, 10:44 PM
Check this info: http://www.marineparts.com/mpf/mpf520.aspx

denverd1
03-14-2008, 11:05 AM
make sure you have head bolts not intake manifold bolts. did you take off a valve cover? or go below it?

head bolts should be tightened in sequence to torqued to specs. USING NEW BOLTS. YOU CAN'T REUSE HEAD BOLTS.

My guess is you have intake bolts, not cylinder head bolts. post a pic, we can help.

TRBenj
03-14-2008, 12:45 PM
I am thinking those 351's used INTAKE manifold bolts to hold the throttle cable bracket in place. If so, the specs for them would be a lot less than a cylinder head bolt...
Agreed- I would say that they used an intake manifold bolt as well. I guess its possible that they used a valve cover bolt, but definitely not a head bolt!

climbinggod
03-14-2008, 08:51 PM
Here is a picture of the rear of the engine. You can see the black throttle cable bracket mounted on the top of the engine. Any help to you? Manifold or head bolt??

Laurel_Lake_Skier
03-15-2008, 07:51 PM
The bracket is not connected by the cylinder head bolts and the torque I listed earlier will be way to high. It is hard to see in the photo but it looks like the bracket is mounted to the intake manifold mounting bolts, the correct torque for them is 23-25 ft/lbs. If the bolts just go into (not through) the manifold then it looks like the torque should be in the 12-18 ft/lb range. I'll be getting up to see my boat next weekend and will check the location then.

climbinggod
03-15-2008, 07:56 PM
I did notice that when I took the bolts out water started to leak out of the crack. Also I did undo the bolts with a 3/8 ratchet and extension.

JLeuck64
03-15-2008, 09:53 PM
Yup, them be intake manifold bolts all right.

Keep in mind that the intake manifold to cylinder head gasket does double duty. In addition to sealing each individual intake runner it also seals some coolant pasages...

If that coolant passage seal is disturbed too much it may create an internal leak. Internal meaning that water would drip down into the valley below the intake manifold and on down to the oil pan. Could create a problem with water in the oil, just be aware.

drbesvold1
03-15-2008, 10:47 PM
where could i get a mc cover for my carburator?

climbinggod
04-14-2008, 08:13 PM
Was there a definitive answer on the intake manifold bolt torque specs from anyone out there??

JLeuck64
04-14-2008, 10:08 PM
The bracket is not connected by the cylinder head bolts and the torque I listed earlier will be way to high. It is hard to see in the photo but it looks like the bracket is mounted to the intake manifold mounting bolts, the correct torque for them is 23-25 ft/lbs. If the bolts just go into (not through) the manifold then it looks like the torque should be in the 12-18 ft/lb range. I'll be getting up to see my boat next weekend and will check the location then.

I would feel comfortable using the specs LLS gave here.

Laurel_Lake_Skier
04-14-2008, 10:42 PM
Sorry....I forgot to get back to this thread. I checked my 91 and the throttle bracket attaches via two of the rear intake manifold bolts, they do go into the head. Torque on those are 23-25. There is also a sequence for tightening but if you just took the two out I think you'll be OK tightening them to spec. and then checking the others.