1983 eldo ht 4100 water pump replacement

[steve eldridge]

hello , working on a 83 eldo ht4100 with a bad water pump. 56,000 miles and just saw coolant streaming from bottom of weep hole. so took everything off front of motor to sheet metal water pump backing plate. no broken bolts, everything greasy and covered in coolant so came apart easily. The sheet metal behind water pump ok, just has white scale , no scoring from impeller. going to spend a day cleaning all greasy parts. removed alt, vac pump, air injection pump, power steering pump and lifted working a/c compressor up to access front of motor. all greasy. Any advice or any thing to watch out for when putting all back together? Radiator has scale so replacing that along with new rad cap and thermostat and rad hoses also. still had the original swollen hoses on car. Also has a bypass hose on water pump to overflow tank. hoping to find a correct water pump. Radiator has oil cooler and trans cooler connections also , soaking those with pb blaster to loosen later. Car didn't have any over heating problems this summer, ran great with ac blasting! What's the best RTV to use with these motors to seal up water pump gaskets? Ok thanks, any advice would be appreciated! 

[Coupe Deville]

I know just what a pain it is to remove those transmission cooler lines. Mine were on there very tight when I had to recore my radiator. I just did my water pump on my 472 Cadillac last month. Once all of the surfaces are super clean, (I used a paint scrapper for the old gaskets, and wiped the mating surfaces with paint thinner to get extra clean before assembly) I ran a bead of blue permatex gasket sealer around the water pump, and the engine side of the gasket. The blue permetex is actually meant for cooling system applications. I then put on the pump and just tightened all of the bolts finger tight. I then left it alone and let the gasket sealer cure for a few hours, per manufactures directions. Then did the final torque with a torque wrench. I know that the 4100 is a diffrent animal from the 472 but the 472 has these 4 little bolts that CAN NOT be over torqued! And they also require a method of being sealed, I used Teflon tape because Scott recomened it and it worked fine. Pick up a factory shop manual too, if you don't have it. It will be a must for this job. I did the whole job without removing the radiator. I really didn't want to do it and there was plenty of room to work around it. Once I removed the fan I covered the whole inside side of the radiator with cardboard, as to not accidentally damage the radiator core. Also, if your radiator and heater hoses are all swelled, just replace them not while the system is drained down.

Best of luck

-Gavin 

[Walter Youshock]

IMPERTIVE  on the 4100 is bolt sequence and torque.  I remember having a small data book that showed the bolt size, location, sequence and torque specs for each bolt. 

I also remember the O rings to the intake manifold leaking on my '82.  Whole thing had to come off just to replace a ring...

[TJ Hopland]

I don't remember any unique issues with the longitudinal 4100's.   The transverse ones were a real pain with what seemed like a thousand bolts but even on those I just remember it being a hassle, nothing really special.