The 4.3L We All Know So Well IIWednesday, August 1, 2012
Editor’s note: Back by popular demand is a column originally featured in Material Handling Network in September 2010.
It is hard to run a service department in 2010 without encountering a GM 4.3L engine. The 4.3L goes way back and has come in many different variations. It has found itself powering Toyota’s, Caterpillar’s, Hyster’s, Yale’s, Clark’s, Hoist’s, Royals, and many other brands of industrial equipment. Vortec, non-vortec, balanced, non-balanced, 4-bolt / 6-bolt intakes, aluminum oil pan or steel? So many differences that it’ll make your eyeballs pop out. Ever have a truck with a broken starter bolt – how much fun is that? We have already done an article on the different variations – but we now have another member of the GM 4.3L family. The following will outline this new engine model which we will all soon become familiar.
At All Industrial Engine we refer to it as the late model aluminum. The first finding of this engine was when a customer had a problem with his motor mounts not fitting on a brand new GM 4.3L engine. Although he didn’t buy the new engine from us he called in to see if we have heard about this problem. He also said that his crank sensor wouldn’t fit. I asked him to email digital pictures and to my surprise the pictures revealed a 4.3L with an aluminum front cover. The rest was history – another new GM 4.3 version was born into the family.
My good friend John Despard from Yale Carolina – Bluff City, who loves to spend his free time identifying the differences in 4.3L’s, was the first customer to have us build the late model aluminum. Assembly was rather impressed with the changes. One assembler commented “GM fixed the problems that the other version had – they didn’t change anything stupid.” Hats off to GM even though I’m not a big fan of Government Motors.
The most significant changes were:
• Engine block – casting #234
• Front cover assembly
• Oil pan and gasket
• Narrow roller rockers
• Crank sensor, cam gear and
• Reluctor wheel
So what’s the easiest way to identify this version? Check for the aluminum cover but use caution – the aluminum front cover may be painted black which can throw you off. You can purchase a crank sensor modification kit that will allow a new engine to run with the old style crank sensor but not vice versa. If you replace the standard vortec with the late model aluminum your future parts purchases on items like the oil pan gasket and crank sensor will not be correct if you go by the model and serial number of the equipment.
It also appears that the late model aluminum engines are being configured with the starter that bolts to the bell housing. This is a superior setup considering all of the broken starter bolt holes that we see on 4.3L engine blocks. Although it doesn’t pertain to the new style 4.3L I thought I would review the issues with the broken starter mount holes to try to help anyone currently battling this for the first time. Here are some bullet points to remember:
• Cracked blocks are very difficult to repair – cut your losses and replace the block immediately. We’ve seen this movie before – trust us - it ends by replacing the block.
• Make sure you use the correct bolts for your block. It can either use 3/8” or 10mm bolts. The wrong bolts will screw in but will wobble and break the block for sure.
• 4.3L starter bolts are not just any old GM starter bolt that you would get from Napa. There are different lengths and too long of a bolt will break out the entire side.
• If you have a customer with a GM 4.3L and the truck hasn’t had a starter support installed – recommend installing one as it can save you and your customer money in the long run.
If you are aware of the issues ahead of time you can take precautions to prevent this from happening in your service department. If you’re PM’ing the customer’s fleet and your tech’s have been replacing starters the customer will blame the dealership for the broken block. It doesn’t matter that this is a weak point with the engine - it will become your problem and it will cost you money.
It is good to be aware of new products as they come to market. We do our best to always keep you informed. If you have any questions regarding this article or any other Tech Talk article please feel free to give us a call at 877/303-LIFT (5438) or email at firstname.lastname@example.org. As always, stay tuned to future helpful Tech Talk articles!