Arrg! Another rod seized

Jim Pelletterie · Posted: Wed Aug 05, 2009 4:23 pm Post subject: Arrg! Another rod seized

I'm sooo tired of this s--t. The engine runs a short morning practice then two ten lap heats then locks up on the grid for the feature. drained briggs /valvoline oil is as green as it was put in. Rod has no discoloration and the bolts were properly torqued. crank & rod was new about ten races ago. This has happened to me twice and numerous times to fellow racers using different oil. What is up with this?

Wayne ONeil · Posted: Wed Aug 05, 2009 9:17 pm Post subject:

Which engine?

Jim Pelletterie · Posted: Thu Aug 06, 2009 6:34 am Post subject:

A gen 4 world formula. never had this problem with the animal

David Klaus · Joined: 25 Mar 2009 Posts: 31

Jim,
Drop me an off line e-mail with your number. You shouldn't be having a bad experience. Let's talk through everything, figure out where your issue is, and get you back on the track.

Dave

Chris Hatch · Joined: 02 Mar 2004 Posts: 405

I have heard of others having problems with the rod, while fortunately I have not. I have never had to clearance a rod and have been running them as stock with about .002 - .003 clearance. Some others I have talked to have been clearance them to .004 or even .006. Of course these are the racers who have been blowing rods so....maybe they are out thinking things?

That said, I am a little nervous putting in the new rod as I have yet to have any failures. My other concern may be with the new crank from China, although I have used a lot of those, they all seem to clearance fine, and have not blown one up yet.

Jamie Webb · Joined: 30 Aug 2001 Posts: 584

#1 - NEVER mix oils. There is NO need for a "break-in" oil. Build it, break it in, and race it with the SAME oil. If you do plan on changing oils, pull the side cover, clean the rod bearing and oiling holes and reassemble with the new oil.

#2 - Get rid of the Valvoline oil. I'm not sure what is going on there, just about every seized rod I have seen and heard of in the last 8 months or so was using Valvoline. I know Briggs and Valvoline did a ton of testing and there are still many people using it without problems, but the problems I am seeing and hearing about are with the green Valvoline oil.

#3 - Check the clearance on your rods..... with a DIAL BORE GAUGE, not a set of calipers. I have seen the good calipers vary as much as .002" between the inside and outside measurements and as much as .005" on the "cheap" calipers. The crank to rod is a critical measurement and in my opinion should be measured with a micrometer and dial bore gauge. No more than .0005" runout and no less than .002" clearance. I like to use .003"-.004" clearance on the WF rod.

#4 - Do NOT polish the crankshaft main journal. If you look at the main journal under a microscope you will see ripples and small holes in the main journal. When you polish it, you remove those areas for the oil to store and ride in. That is OK for an automotive engine where you have forced oiling and babbit bearings, but not for our karting engines.

The above information should solve any problems you are having. It has served me VERY well with running the WF rods. They are the ONLY rods I run and since doing the above, I have had ZERO problems.
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Jim Pelletterie · Posted: Thu Aug 06, 2009 8:30 pm Post subject:

thanks for the tips, I used muriactic acid to remove the aluminum from the crank. whats the best way to clean it up or should I just buy another? And did I read somewhere that the price of the WF rod was lowered or was that just a dream?

Jamie Webb · Joined: 30 Aug 2001 Posts: 584

Replace the crank & rod. You are only asking for trouble if you re-use them.

The WF rod and Animal crank should both be $55 each.
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Jamie Webb
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Jim Pelletterie · Posted: Fri Aug 07, 2009 1:11 pm Post subject:

No one I find has a WF rod for 55.00. The best price I found is 68 bucks. Does any aftermarket source make a billet rod with inserts for this engine?

Wayne ONeil · Posted: Fri Aug 07, 2009 1:33 pm Post subject:

Comet Kart Sales has it for $59.

http://www.cometkartsales.com/store/briggs/wf-block.htm

Jamie Webb · Joined: 30 Aug 2001 Posts: 584

http://karting.4cycle.com/showthread.php?t=236796
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Bob Vehring · Posted: Sat Aug 08, 2009 7:42 am Post subject:

Jim, Personal opinion here but I have never liked or had as good luck with rods with inserts. Two reasons, one, by the time they open up the big end large enough to fit in the insert, they have taken away much of the strength of the rod. Two, the insert, being of softer material has the possibility of going out of round easier or getting a piece of dirt, metal, whatever stuck in its softer surface causing a hot spot.
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Jim Pelletterie · Posted: Sat Aug 08, 2009 6:42 pm Post subject:

I know I or our club members are having a problem with distroying a rod for no apparent reason. could this be a metallurgy problem? Last season I went thru three. Clearences are double checked and usually the engines run flawlessly until, wham, the rod sticks. We used to turn the animals tighter without problems and use cheaper oil. As you might tell I'm somewhat frustrated. We run four karts with the WF and I have a spare in the trailer. The spare gets used more than i'd like.

Clarence Carter · Posted: Sat Aug 08, 2009 7:55 pm Post subject:

The rods are seizing because you are racing a lawn mower engine. Laughing

Just ribbing you guys. I like seeing Briggs involvement in karting. I think they are doing a wonderful job. Can you tell if the rod is seizing on one side of the journal vs. the other side? Maybe there is a twist or a side load going on there.
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Jamie Webb · Joined: 30 Aug 2001 Posts: 584

If you are checking the clearance the way I said (micrometer & dial bore gauge) and still having problems, it is the oil. Also, like I said, make SURE no one is polishing the crankshafts.

Once you know you have the right clearance, use one of the following oils and I will bet your problems will go away. FHS Hurricane Medium or Thor Lite or Heavy. I know guys using both of those with MANY HOURS of racing with zero problems.

There is nothing wrong with the WF rods.
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Jamie Webb
Call or email for Home, Auto, Life, or Health Insurance quote (Florida only).