Rod bolts?

[mercrazy]

Are stock 2.5 rod bolts safe at 7000 rpm?
What about used ones?
Are WSM standard bolts the same as Promarine, Buckshot, etc.?

[LakeFever]

Depends on who you ask. Rb8000 from promarine is the popular choice. They are priced well and strong. Never re-use a rob bolt on a performance motor imo it’s not worth the gamble. Don’t use the 90 degree ones either. I used rb8000 and torqued down in three stages ending up at 35lbs with red lock tite. Be sure to hone your rods and replace the needle bearings too if you pull the piston off

[rock]

I have re-used rod bolts forever. If they won't hold torque, you will feel it.

Rock

[LakeFever]

Your braver than I. For the record you cannot reuse the tty ones that some motors come with. Those are a one time

[skialot2]

Torque to yield bolts should never be reused. The manufacturers of the bolts tell you not to. They are designed to stretch to achieve the proper yield. If you reuse them, they are over stretched. Over stretch anything and it is weaker then designed. ProMarineusa.com is selling the RB8000 rod bolts for $3.95 each. For that price, is it worth taking a chance on windowing a block reusing a bolt?

[rock]

I have only been doing this for 40 years or so, built a hundred or more engines, and have never had a rod bolt come loose. I am not arguing that mercury doesn't recommend re-using tty bolts, just saying what has worked for me.

Rock

[tlwjkw]

I have only been doing this for 40 years or so, built a hundred or more engines, and have never had a rod bolt come loose. I am not arguing that mercury doesn't recommend re-using tty bolts, just saying what has worked for me.

Rock

stock production motors agree but i never TTY anything, pulled a few threads outta tha block.. use torque numbers... jus never old things in/on any kinda "hot rod" for me... like Rock, got away with it for years n years n years.... jmo.

[mercrazy]

I have mixed feelings on used parts. I wouldn’t reuse the stretched bolts. I’m not racing so good used 30lb bolts should be ok. I’ve run one engine for 30 years with used bolts. Turned it 7100 rpm.
As for rod bearings, I have faith in used ones after close inspection and cleaning. I’ve torn down more than one engine with rod bearing rollers that fell out in pieces. And these were metal caged with no damage to piston.
My thought is you never really know how good a part is until it’s stressed.

[skialot2]

I’ve torn down more than one engine with rod bearing rollers that fell out in pieces. And these were metal caged with no damage to piston.

The older motors came with metal rod bearing cages where the rollers are loose. You have to place each roller in the cage as you assemble the rod bearing. The newer metal cage bearings the rollers stay in the cages.

[mercrazy]

The individual roller was crumbled. It was still in place, just in pieces.

[hooken203]

Make sure you understand the difference between tty bolts and angle torque bolts. There is a difference.

[pcrussell50]

Make sure you understand the difference between tty bolts and angle torque bolts. There is a difference.

^^^This^^^ cannot be stressed enough.

It's right there in the name. Once a steel bolt has yielded, it will not be the same again. If you torque a non-yield/stretch-bolt to yield, you will probably pull out threads.

-Peter