May Tech 101 Article

By:Fran Pepi

Control of engine temperature is critical to the consistent and predictable operation of a bracket engine. Having the water pump run independently of the engine gives you 100% control of coolant temperature. It also can save you fuel during initial warm-up by hastening the process. Years ago I installed a water pump drive on my 455 Olds motor. It was a great upgrade but there was one problem. With the alternator in its stock location, the elimination of the water pump pulley created a long run between the alternator and crank pulleys. All I could imagine was tossing belts at higher engine speeds. With the engine out and on the stand over the winter months, it gave me time to come up with a solution. I really didn’t want to relocate the alternator, mainly due to the fact that at the time there wasn’t anything that I knew of available and also knew there had to be easier/cheaper way. Being a dealership technician by trade, I see many different serpentine belt configurations with their idler and tensioner pulley setups and that gave me an idea for a solution to my problem. I figured I could use some sort of idler pulley that would apply pressure on the top of the belt at about half span. I ended up using an actual tensioner/pulley assembly from a late model truck which was in the late 90‘s. It was fairly easy to adapt it to the front of my motor with a fabricated bracket. It has been on my car over 8 years now and has worked flawlessly. It is a low buck, which I like, fix to a problem. With the pulley riding against the top of the belt, I found that you need to run the Top-Cog type belt from Dayco which has grooves running perpendicular to the belt surface. One time I replaced the belt with a regular v-belt and it threw the belt on a run. The reason I think this happened is that the belt without grooves literally “hydro-planed” on the pulley due to air being trapped between the belt and pulley surface. The grooves don’t let the air build up. That was the ONLY time it ever tossed the belt and I have run the Top-Cog ever since without issue. With this setup, you never worry about belt tension because it’s automatic. The less work/maintenance I have to do, the better! Questions and comments are welcome and can be sent to me at FP442@aol.com

By: Fran Pepi