1998 Ford Explorer 4.0L V6 OHV Engine

[CynthiaK]

Thank-you for the reply. We double checked that and no leaks. We replaced the water pump too so all brand new.

 

[CynthiaK]

I have had similar issues to your 'not obvious' leak. My wife's Explorer was leaking from thermostat and then water pump (not doing checks). I replaced the water pump and she ignored doing checks. Needless to say, replacement water pump became trash in a couple of months. Long story to the point, pressure test the system to find your leak/leaks and read directions on sealants some require 24 hours before service. Do not post repair pressure test within that window. Make sure to replace or clean out your overflow hose. After, check coolant COLD, at the radiator, a minimum daily. Make sure, if possible, to park facing up hill. Do about a week of daily checks. Add coolant, as required. Then, weekly, at bottle should be enough. Every quarter thereafter check the level at the radiator.

 

[CynthiaK]

Thank-you for the reply. We have been checking everything cold before we drive it each day. We did add some K Seal and the leak has pretty much stopped. Just a drop here and there now compared to a stream.

 

[CynthiaK]

@CynthiaK

Who many miles on your Ex's OHV engine?

My guess is your leak is probably the Timing Cover Gasket - a weak link the OHV

The first time this showed up on my Ex was at 13 years, 165,000 Miles.

The coolant system was very well maintained - but eventually the service life of the part is reached.

The timing cover gasket is super thin AND has A LOT of WEIGHT on it = timing cover, water pump, fan clutch and fan.

Highly suggest that you use the original green Teflon coated OEM timing cover gasket, available off of Ebay (part number in linked write ups).

Also, set aside a couple of days - it's all in the write-ups - especially the 2nd one

Link 1: Removing timing cover on 4.0 OHV

Link 2: 4.0 OHV Timing Cover & Gasket Issues

Hope that helps and good luck!

 

[CynthiaK]

It has 170,000 KMs.

 

[CynthiaK]

Thank-you for the response. Brand new water pump, no leaks

 

[CynthiaK]

@CynthiaK

Who many miles on your Ex's OHV engine?

My guess is your leak is probably the Timing Cover Gasket - a weak link the OHV

The first time this showed up on my Ex was at 13 years, 165,000 Miles.

The coolant system was very well maintained - but eventually the service life of the part is reached.

The timing cover gasket is super thin AND has A LOT of WEIGHT on it = timing cover, water pump, fan clutch and fan.

Highly suggest that you use the original green Teflon coated OEM timing cover gasket, available off of Ebay (part number in linked write ups).

Also, set aside a couple of days - it's all in the write-ups - especially the 2nd one

Link 1: Removing timing cover on 4.0 OHV

Link 2: 4.0 OHV Timing Cover & Gasket Issues

Hope that helps and good luck!

Thank-you for the reply!