V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

[Greg_E]

I am in the process of rebuilding a 1988 225 HP powerhead. I had mentioned to Faztbullet that the bottom crankcase head bolts were severely corrode, and he recommended that I upgrade to the bolts used in the 2001 engines. (I'm talking about the bolts for the upper and lower crankshaft bearing carrier assemblies not the cylinder heads.) They are equivalent to a grade 7 and are stainless steel (I think). I thought that was a good idea, until I looked at the price from Evinrude. $10.96 each times 16 bolts.
I could not find any grade rating for stainless steel bolts, but I did find listings saying they were equivalent to or exceeded grade #.

I checked McMaster Carr and found these.
Extreme-Strength 12 Point Flange-Head -Stainless Steel
1/4-20 x 3/4" , 96242A506 $2.00 each
1/4-20 x 1" , 96242A509 $2.18 each
They are stronger than a grade 8 bolt, and much more affordable
Up to 1" long they are Type 304 stainless and over 1" long they are Type 450.
http://www.mcmaster.com/#standard-cap-screws/=lgiasc

I have not purchased these yet, but I don't see why they wouldn't be a suitable alternative. Just passing this along for anyone rebuilding a powerhead looking to save a few $$$. They are about the same price as the OEM grade 5 steel bolts that will rust. and $9.00 less per bolt than the OEM upgrade stainless steel bolts used on 2001 and newer.

Update: 2/14/13 I received the bolts today. They are manufactured by ARP, a company recognized for high quality fasteners. I did some reading on the ARP site. They use a proprietary process involving power dumping to strengthen the bolts. 304 stainless cannot be heat treated so this other process is used to strengthen the bolts. The twelve point head is the same as the rod bolts so you won't need a special socket.

Excerpt from ARP catalog:

"17. Define “Power Dump.”

This is a term used to define the heavy extrusion of the fastener body during forging. The part is forced into a die much smaller than the blank thereby causing a severe reduction in cross section area. This reduction of the cross sectional area is accompanied by an increase in length because metals can’t be compressed. However, power dumping or reduction, delivers a significant increase in strength properties and is part of the patented process we use to produce fasteners from 304 stainless steel with 170,000 psi UTS........."

 

[multimech]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

!/4" 20 is not a head bolt size. The only head bolts I have ever pulled on a Johnson or Evinrude is 5/16". I think you need to go back and check your sizes.

To answer you question...sure why not? Head bolts are for outboards are not like the head bolts in a 4 stroke engine. Using the same or better strength, with the stainless is in no way a problem. Just make sure they are the right diameter and the right length.

 

[Greg_E]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

The crankcase head assemblies. upper and lower. Not the cylinder heads.

I added info to my original post. I can see why you were confused. Evinrude calls the parts "crankcase head" assemblies not me.

 

[bob johnson]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

your head bolts will easily be over 1", more like 2" or more i bet.

i also agree the head bolts are bigger than 1/4-20.... they are either 5/16ths or 3/8ths " dia.

you dont need grade 8 bolts i bet..... the head uses many bolts....but normally SS bolts are weaker than allow steel.....

the reason the bolts break usually is the motor was run in salt water and the bolts corroded into the aluminum...

you need some form of anti-sieze....

good luck

bob

 

[Greg_E]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

Just to clarify, I am talking about the bolts for the bearing carrier assemblies for the crankshaft. Upper and lower.

FYI. if you use the wrong type of anti-seize compound in saltwater you can actually make the problem worse. Some compounds have powdered metal in them that can react with the aluminum. When possible I use either a non-hardening gasket sealer on the threads or a good marine grease.

Cylinder head bolts are lubed with 2 stroke oil prior to torquing the bolts. Use anything else, and it can skew the measured torque value.

 

[Chris1956]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

Stainless steel bolts are grade 2. Read the marking on the original head bolts and replace them with equivalent rated bolts. if they are stronget than grade 2, they need to be steel. Use some blue locktight or Permemtex #2 to seal the threads.

 

[Greg_E]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

Stainless steel bolts are grade 2. Read the marking on the original head bolts and replace them with equivalent rated bolts. if they are stronget than grade 2, they need to be steel. Use some blue locktight or Permemtex #2 to seal the threads.

Did you even bother to go to the McMaster Carr site and read the specs. for the bolts I listed?

 

[multimech]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

Sorry Greg_E, I sometimes read or hear stuff and jump the gun. To be honest I wouldn't worry so much about the strength of them as much as the quality of stainless they are rated at. I have taken a lot of these engines apart that had no stainless bolts and it is a pain the ***. They basically just hold the carrier in place. They are also secured by the four screws (bottom carrier) which preloads the bearing. They are also held in place by compression of the cylinder halves. On the top carrier, be sure to loctite them in place. I have seen them loosen and then wallow out the holes, making the block junk. Hope I have a handle on what you are doing now.

 

[Greg_E]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

No need to apologize. When you read head bolts you just naturally think cylinder head bolts. That's why I went back and edited my first post.
When I disassembled the power head, it was a PITA to get the lower bolts out because the heads of the bolts were severely corroded. For about the same price as the OEM steel bolts, I'll use the Mc Master high strength SS just to avoid having to go through that again. $11 for a 1/4-20 x 3/4 SS bolt is just outrageous.

I will be sure to use thread locker.

Couldn't the holes be repaired with a helicoil or insert? I'd hate to scrap a block just for that.

 

[multimech]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

I come from a professional standpoint on repairs and that could be done, but not cost effective or reliable enough for shop work. Because the surface on top needs machining most of the time and the inside area of the block gets gouged, often and is very hard to repair, because it is bored through the center of the block and must be the same spec all around.

However, you may not have the problem to begin with. If they are alright, simply locktite them, and torque them to approx. 100 to 110 inch pounds. You will be fine. These are just the top carrier bolts.

 

[multimech]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

I know what a PITA the corroded bolts are, believe me.

 

[Greg_E]

Re: V6 Looper Crankcase Head Bolts: Possible Cheaper Alternative.

I had ordered some of the bolts from BRP when I disassembled the motor to replace the corroded ones. I ordered the 1988 bolts not the 2001 bolts which are much more expensive. I never looked at them until today. The old ones were grade 5 steel bolts. What they sent were what appears to be off the shelf 18-8 stainless bolts. Some have only a manufacturer's mark. A few had nothing. A couple had grade 2 markings. There are three different manufacturers in the lot of 8.
I guess BRP doesn't think you need a grade 5 or better bolt now.
The torque spec is quite low when installing these bolts. I think you would tear out the threads in the block before you snapped even a grade 2 bolt.
Having said that, I'm using the ARP bolts from McMaster Carr. For the same price as the 1988 bolt, it's a better bolt than even the 2001. If that doesn't work for you , just go to your local hardware store and get some 1/4 -20 x 3/4" SS bolts, because that's what your going to get from BRP.