Replace Rod Bolts on a 3.2 - what does it take

[JeremyD]

My case is currently closed. My jugs and pistons are off - these voices keep whispering in my head (as well as a few emails) to change my rod bolts (now that I am this far along).

How much more work to replace my rod bolts?

Will the rods need to be machined to accept the 10mm vs 9mm bolts?

Can I crack the case, change the rod bolts then button it back up without doing anything else (57,000 on the motor)

What says you?

[MotoSook]

("what does it take")

PATIENCE!

And 9mm rod bolts from ARP...no machining.

[88911coupe]

Is this a "simple" replacement process or are there things you have to do such as replacing the bearings or shims or whatever and measuring the journals?

[JeremyD]

Hadn't planned on opening the case - 98mm jugs -

Really don;t see the need to - so would just split - replace rod bolts - and button back up

[asphaltgambler]

Yes take my word!! Replace those rod bolts!! That's what failed on my 3.2 1200 miles after I bought it. PO probably ran the p*ss out of it and stretched them for me. My great luck!

I have had P-engine builders tell me that installing the ARP bolts will slightly distort the big-end of the rod because the shoulders are larger OD. After installing them and torquing, the big end should be checked for roundness.

[Tyson Schmidt]

You really should split the case to replace the rod bolts with ARP.

Technically, you can replace them without splitting the case, but I don't recommend it. If you were using stock rod bolts, then you can do it.

But the ARP bolts should be installed using a stretch gauge, and only with a stretch gauge IMO. And that requires the crank to be out of the case.

[cjr1]

I'm replacing stock bolts w/ ARP bolts & have a bit of info regarding torque procedures.Everyone seems to be in the stretch gauge camp,which I'm also inclined to follow.

In the package of rod bolts there are stretch #'s for bolts,but there is also another procedure for torqing the rod bolts.
It states"torque to 35 ftpds,loosen,torque to 35 ftpds,loosen,torque to 35 ftpds,then check length with mic for appropriate length(measure before & after).

Anyone ever try this way or opinions on this?

Jeremy,Do the rod bolts if you can.CHEAP INSURANCE!

My.02

Chris

[ChrisBennet]

A couple of data points:
1) If you call up ARP or Raceware I think they'll tell you that something like 90% of their customers just use the torque angle method.
2) If you use the torque method and follow the manufacturer's directions you'll find that they are stretched less than the minimum stretch spec'd by the manuf. At least that has been my experience.
-Chris

[vichang4]

I replaced the rod bolts on my 3.3 turbo with ARP bolts without splitting the case. The engine had 50,000 miles, so there was no reason to split the case.
The bolts can be removed and the new bolts installed one cap at a time. Hold the bolt in place with a long screw driver from the back side of the case. I torqued, loosened, and retorqued the nuts 8 to 10 times with the ARP lubricant before the final torque. I checked my torque wrench for accuracy and torqued the nuts to the highest recommended torque value.
The engine has seen about 5000 miles and 5 or 6 track days without any problems.

[BReyes]

Jeremy:

I would ask Frank Eibell for input, as he is very close to you, and could offer advice/ render professional services.

It seems as if you are (1) fixing something that is not broke, or (2) entering total rebuild territory.

I would also speak with another local (in Tampa), Dave White.

You can corroborate what they say should you choose to seek outside help.

Regards,

[JeremyD]

yes yes all reputable guys in Florida - all more than willing to seperate me from my cash - all will say - yeah, while the engine is out...

[Tyson Schmidt]

The torque method is playing Russian Roulette, IMO.

I've always used the stretch method, and have come across a few bolts that reached torque WAY before they reached stretch spec. If I hadn't been using the stretch method, they definitely would have failed.

A better way would be to figure out what angle would yeild the proper stretch. Say, using a stretch gauge, torque the nut to 10 ft/lbs. Then watch the angle needed to reach stretch. That would be a safe alternative to the stretch method.

But I'll never use the torque-only method on these fasteners, based on my own experience, and some horror stories from others.

[BReyes]

What I meant was, leave RBs as is until you are doing total rebuild. If you spoke with Frank about what you are doing, I would venture he would say the same thing.

[adomakin]

anyone know where i can get a stretch gauge from? im looking at sites over here (uk) and can't find anything

Andy

[JeremyD]

From the ARP website
http://www.arp-bolts.com/pages/tech/fastener.html

[blue82coupe]

Hey guys.. does this mean you can't reuse ARP rod bolts,on later rebuilds? Dan