1998Exp
Explorer Addict
- Joined
- December 5, 2010
- Messages
- 1,340
- Reaction score
- 206
- City, State
- Seattle WA
- Year, Model & Trim Level
- 98 Limited V8 AWD
As many of you know, sooner or later many of our 5.0L engines will start leaking coolant from the top of the timing cover. This seemingly simple task has many gotchas, which had been discussed here numerous times.
My 98 Exp started leaking at around 140K, and I posted the details from the experience on this forum around Jan 2011. All looked good at first, but soon oil started dripping from the bottom of the timing cover, where it meets the oil pan. The leak was small enough to not even need adding oil between changes, but the mess at the bottom of the truck drove me nuts, and I finally decided to repeat the task. Here are some points from that experience:
1) You don't have to remove the radiator (which is a huge hassle!). The main challenge is finding a harmonic balance tool with a short enough bolt to fit in the space. Performance Tool #W98711 is really nice and fits perfectly. This tool is much better than the primitive removers/installers that auto parts stores sell. My local O'Reilly used to rent it, but doesn't anymore. Found it online for about $60. Good investment!
2) For those who have access to a compressor, removing the center bolt is a breeze, but with the radiator in place you need a very compact impact wrench. I have a 'Klutch' brand (no part number), which is just 4" long. Not a great tool, but great for this job.
3) I originally assumed that I can just apply some black RTV on the top of the original pan gasket, and it will seal. Big mistake: sliding the timing cover wiped much of it off, causing the leak. This time I followed the instructions that came with the Felpro gasket kit, cut the original gasket at the front of the block and glued their two cork pieces. Ugly, but it works! I torqued the pan bolts to the specs in the manual, which were obviously written for the steel gasket, so it squeezed the cork way too hard. If I had to do this again, I would not go above 10 ft*lbs.
4) The OEM spring-type hose clamps are, in my opinion, much better than the aftermarket worm screw type. The clamping pressure for the former comes from the spring, while the screw type relies on squeezing the hose. Once the rubber shrinks a bit, the pressure is gone, and a leak develops. You then tighten the screw some more, and the story repeats until the hose is damaged and needs replacement. Sadly, with all the obstacles around the bottom of the water pump, my tool wouldn't fit, and I had to use the screw-type clamp. If anyone has a trick, I will be happy to know about it.
5) Just a couple weeks before starting the job I replaced the oil filter with the fancy Mobil-1, so saved it for re-installation. The thing just wouldn't seal! Learned that on oil filter gaskets (including the expensive Mobil 1) are made from cheap rubber and not intended for repeated installation.
Hope this helps someone. Good luck!
My 98 Exp started leaking at around 140K, and I posted the details from the experience on this forum around Jan 2011. All looked good at first, but soon oil started dripping from the bottom of the timing cover, where it meets the oil pan. The leak was small enough to not even need adding oil between changes, but the mess at the bottom of the truck drove me nuts, and I finally decided to repeat the task. Here are some points from that experience:
1) You don't have to remove the radiator (which is a huge hassle!). The main challenge is finding a harmonic balance tool with a short enough bolt to fit in the space. Performance Tool #W98711 is really nice and fits perfectly. This tool is much better than the primitive removers/installers that auto parts stores sell. My local O'Reilly used to rent it, but doesn't anymore. Found it online for about $60. Good investment!
2) For those who have access to a compressor, removing the center bolt is a breeze, but with the radiator in place you need a very compact impact wrench. I have a 'Klutch' brand (no part number), which is just 4" long. Not a great tool, but great for this job.
3) I originally assumed that I can just apply some black RTV on the top of the original pan gasket, and it will seal. Big mistake: sliding the timing cover wiped much of it off, causing the leak. This time I followed the instructions that came with the Felpro gasket kit, cut the original gasket at the front of the block and glued their two cork pieces. Ugly, but it works! I torqued the pan bolts to the specs in the manual, which were obviously written for the steel gasket, so it squeezed the cork way too hard. If I had to do this again, I would not go above 10 ft*lbs.
4) The OEM spring-type hose clamps are, in my opinion, much better than the aftermarket worm screw type. The clamping pressure for the former comes from the spring, while the screw type relies on squeezing the hose. Once the rubber shrinks a bit, the pressure is gone, and a leak develops. You then tighten the screw some more, and the story repeats until the hose is damaged and needs replacement. Sadly, with all the obstacles around the bottom of the water pump, my tool wouldn't fit, and I had to use the screw-type clamp. If anyone has a trick, I will be happy to know about it.
5) Just a couple weeks before starting the job I replaced the oil filter with the fancy Mobil-1, so saved it for re-installation. The thing just wouldn't seal! Learned that on oil filter gaskets (including the expensive Mobil 1) are made from cheap rubber and not intended for repeated installation.
Hope this helps someone. Good luck!
