My buddy has a 1990 Accord. A few weeks ago it was overheating so we flushed the cooling system and started preparing to replace the radiator and water pump. (I had no idea at the time that the water pump was run off the timing belt). We got the thermostat off and it had obviously failed (it was all mangled up and clearly the culprit). At that point, rather than continuing to tear the car apart we decided to replace the thermostat, flush the system with the prestone kit, fill it back up and see if that did the trick.

Apparently it did for a while...but...he called me the other day and said that it overheated again and when it did he turned the interior heater on high and it did not blow hot air. He took it to the shop and they said it was the water pump. My buddy isn't very car saavy and couldn't really give me any more detail on exactly what the symptoms are other than its running through coolant (but he can't find any leaks) and it's still overheating. I'm pretty sure the guys at the shop just gave it cursory glance and I don't have a lot of faith in most of those guys anyways, they're not exactly objective.

Just for reference here: I'm certainly no expert but I'm not afraid to tear apart an engine. I've done a full engine swap and I replaced the clutch on my Jeep a few weeks ago. I've done several common style exterior mounted water pumps and radiators, etc. Honestly, when my buddy told me that the water pump is "inside the engine" on this car I thought he was smokin crack and must have misheard the guy at the shop.

So....I'm going back over there this weekend to help him out and see if we can't get this thing back in good order.

What I'd like to know is: how can I test and trouble shoot this thing to confirm that it definitely is the water pump? The fact that the heater would not blow hot air when it was overheating is seeming like a good indicator that the pump is out...then again the t-stat could be stuck closed or maybe the heater core is also clogged up in addition to whatever is causing the overheating problem....but I'd think that if the heater core was leaking he'd of noticed a puddle under his car.

I figured maybe we'd start by running it and looking around for leaks then if nothing was noticeable we'd run it without the radiator cap to see if any fluid is flowing, and take off the cap on the tee fitting from the prestone kit to see what kind of pressure is flowing through the system. Does this sound like a good place to start?

If we take off the timing belt cover should we be able to get some indication by checking for leaks and listening for it to squeal or grind or something?

While we're at it we may as well test the cylinders for compression and make sure he hasn't blown his head gasket and if I can talk him into spending the cash we'll replace the radiator after the water pump, because if it's clogged up and the pump is having to work extra hard against it then that'll just cause the new pump to fail again prematurely....

Soooo...sorry for the long post, I'm kind of thinking out loud here....does all that sound like a reasonable plan and anybody want to add anything to it? Any help would be hugely appreciated! I hate working on other people's cars because if I overlook something or something messes up I'll feel like a real jerk...

thanks!

 

welcome to the forum. If the cooling system is overheating, check to see if the fan motor is working. at approx 3/4 scale the fan motor should kick in to cool the radiator. If you take the timing cover off, you will see the timing belt, cam pulley ( big round one) and the water pump mid area. Go to autozone.com and sign in for free and you can navigate to repair timing belt or water pump. you will see how to do all you need. Just a heads up, the timing belt on the lower crank pully to get off the nut is tight and hard to get to. If you can change a clutch, you can change the timing belt. just make sure its at top dead center and lock up the flywheel to not turn when you take the crank pully nut off to change the belt, since you may change the water pump if it leaks. ask all the questions you need to.