Suggestions to find coolant leak

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b5cuda

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Hi all, trying to chase down a coolant leak. Steady drip at front passenger side corner of the lip of the oil pan (see arrow). I already replaced the lower hose (radiator to water pump) as it looked pretty worn, but that didn't fix the problem. Engine is dry on top where water hoses connect. Am I looking at waterpump, or timing cover next? Engine is a 340, the car is jacked up so that front wheels are off the floor. Appreciate any suggestions - thanks!
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Take the fan and top pulley off and put you finger on the bottom side of the pump. There is a weep hole there see if your finger gets wet at that hole. That is the first place I would look.

Where the water is coming off it could be Water pump gasket , timing cover gasket, thermostat Gasket or the intake gasket. I have seen a loose timing cover bolt leak coolant from the threads.
 
A pressure test is the ticket. maybe freeze plug or timing cover ??
 
Thanks guys, appreciate the thoughts! I will look into a pressure testing kit. I'm thinking a new waterpump is cheap so may just swap that out.
 
You can also buy a fluorescent dye kit at your parts hose and test using the supplied black light. it will show you where the leak is.
 
Water pump mount bolts screw into the water jacket. Drain the coolant down. Remove bolts one at a time, clean, dry, blow out, and re seal threads with aviation sealer or high tack, screw back into block.

Or like you say, replace the watet pump, and get it all resealed at the same time.
 
take it to the coin wash, soak it with engine de-greaser of you choice and blast the gunk off it first. wrap alt and dist with plastic wrap. also take a large piece of cardboard to lay on so you can get underneath with the sprayer
 
Great tips guys, thanks! And it is does need a good spring cleaning
 
Here is my take on it. If pump had never been off, its pump or gasket. Get a timing cover gasket set. Do the chain while you are in there. Several times i have replaced pumps only to have go back and replace timing cover gaskets short time later.
Seems like when the pump bolts have moved, the leaks will show up.
 
If you're just trying to find where it's from, a trick my Dad used was to clean it all good, then coat everything with flour or baby powder. Run it a minute or two. Green coolant shows up nice on the white.
 
Most big box auto parts store will loan you a pressure test kit in hopes of selling you replacement parts. That way u can be sure on the cheap, unless you use a pressure test kit alot.
 
Follow-up: thanks for the great tips! I've pulled the waterpump and now pretty sure the leak was coming from the timing cover, so plan to remove and reseal. Just wondering, should I also drop the oil pan to get proper seal on the timing cover? And if so, can the oil pan be dropped without lifting the engine? Was thinking I might be able to do it if I pulled the drag link bar... Mission-creep is setting in!
 
I had a leak from the front freeze plug on my passenger side head, this was on a BB, don't know if the 340 is different.
 
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