What problems can leaking waterpump cause?

What problems could a leaking waterpump cause? I am a little concerned because I changed my timing belt and at 75,000 miles and I didn't change the waterpump. So far I have no leaks (knock on wood) and I have 86,000 miles on it. Another question, I did a full tune up and my rpm's sometimes drops from normal 600 at a stop to 500 and then back. Seems like the engine is ever so slightly stalling, not a big deal, but annoying. Feedback greatly appreciated.

Could contaminate the oil, could contaminate the timing belt. The belt will break eventually. Contaminating the oil could trash your engine if you let it go. Keep an eye on the ground under your engine for antifreeze leaks.

For the idle issue, check the computer for codes. If there is none, don't worry about it as long as the engine drives well.

I had a leak inthe radiator that I had fixed, but I noticed that some of the fluid was spread all over the engine. I don't know but I read somewhere that you can clean the MAF sensor. If the MAF sensor was contaminated, could I do this, and would it cause the idle to dip a little. Also, is the MAF sensor the sensor that is a little after the stock air box, it is plugged into the hose with a few wires coming out? I have a 98 4Runner, V6.

A leaking waterpump will NOT contaminate engine oil. When a waterpump leaks, it leaks externally, not internally. It will leak down the front of the engine, down onto the outside of the front of the engine. Typically coolant leaking from the waterpump will not make it to the ground, it dries up before it reaches the ground.
Coolant also does NOT contaminate the timing belt. If the pump locks up, the belt will most likely be damaged, but in my 8 years of Toyota experience, I have seen maybe 1 or 2 that actually locked up. Keep an eye on the pump to see if it leaks.

Sorry for the confusion about getting in the engine oil, I guess I was thinking of another engine.

Seems that a leaking shaft would contaminate the timing belt if the leak got much beyond a drip leak. Also, you certainly would see the antifreeze on the ground at that point.

You can look down at the corner between where the lower timming cover and the thermostat housing usually you will see little red crust of coolant there if your pump is leaking. Also I have never seen coolant make it to the floor out of the waterpump usually it just builds up inside the timming cover. I have also seen it to where it has been leaking so bad that it goes down onto the crank pulley and messes up the readings from the crank sensor .

I just did a timing belt job (all belts, pullies, tensioners, water pump and all that good Toyota stuff) at 145,000. It was the original water pump and it was working just fine. I just figured, two timing belts......it was time for a new water pump. I didn't want to push it too far. I say just keep an eye on it.

I'm having my V6 95' 4runner's timing belt checked and replaced if need be this Wed. Just bought the truck this past fall, was told it was done, but don't have any proof. She just turned 90K. Are there any other parts I should have the mechanic look at and/or be warned of any popular mech schemes in that area. I have read you should do water pump with belt? I am more use to the toys 4cylinder and am new the the V6.

I'm having my V6 95' 4runner's timing belt checked and replaced if need be this Wed. Just bought the truck this past fall, was told it was done, but don't have any proof. She just turned 90K. Are there any other parts I should have the mechanic look at and/or be warned of any popular mech schemes in that area. I have read you should do water pump with belt? I am more use to the toys 4cylinder and am new the the V6.

A common failure with the 3VZE engine (3 liter,V6) used in about 40% of the 1988-95 4-Runners/pickups is the idler bearings seize up so most folks replace them when doing the timing belt:

http://www.off-road.com/toyota/tech/v6tbelt/index.html

Sidney® ™
Repairs tv's,vcr's,home/car audio out of my home
E-mail:sidneybek@yahoo.com
Dartmouth,Nova Scotia
Canada
1985 Toyota 4-Runner,solid front straight axle,factory cruise control,sunroof,22R-E,W56,RN60LV-MSEK,rusted rear step/towing chrome bumper with 249 000 KM

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