4.2 Leaking Lower Intake Manifold Gasket Question
 

I had my coolant level marked off on the reservoir ever since I purchased my 98 F150 4.2 V6. It has an engine build date of Jan 5, 1998 (bad luck on my part).

I noticed a small amount of coolant loss in the last 2 months and there is a small trace of coolant on the oil filler cap. It smells like coolant and looks like coolant. The oil was changed and it looks fine in texture and colour and smell but I suspect it may have a small amount of coolant in it. I had taken the plugs off twice and I do not see any coolant on any of the plugs but the plug from #1 is whitish compared to the other plugs. Car starts and runs fine. 156,000 kms on it.

Is it possible for a leaking lower intake manifold gasket to leak coolant into the engine oil and very little or nil amount of coolant into the combustion chamber?

I guess my problem is trying to figure out if my coolant loss is from the lower intake manifold gasket or the front timing chain cover. There is no external coolant leak on the timing chain cover. I am hoping it is the lower intake manifold gasket as I will be taking it into ford to get that fixed on Monday and then I would do the work myself on the timing cover gasket during the spring/summer when it is warmer.

I would have them both done at the same time. Why gamble, sounds like the timing chain cover has given way. If you scroll through the many post on the topic, it is always recomended to do both, not one or the other, a little insurance sure beats the heck out of a rebuild.

Got the lower intake manifold gasket replaced last month. Coolant level not dropping anymore and no more signs of coolant/milk shake on the oil filler cap.

Sounds Good, Glad You Were Able To Catch It In Time. I'm Sure A Sense Of Paranoia Has Set In About It, Just Keep Eye On It For Awhile Till You're Totally Satisfied.

Don't risk it
 

Yeah, I started noticing a white puff of smoke out of my exhaust, and shortly later my oil pressure started to drop, first just while shifting(have a manual) then it became completely flatlined within a few days. Turns out my mains had become worn because of the the small coolant leak. I was only loosing 1/2 a gallon every few months. So, Im not so lucky, but in a way I am but I will 2600 bucks for a Jasper engine!

PS 97 F150 4.2, 140,000

I was lucky there was this forum. Before I buy a used vehicle, I general search the web to get info on what problems they have so I knew about the hydrolock issue from this forum before I purchased the vehicle and just keep an eye on the coolant every month after I purchased it. As well, I go the dealer to change the tyrods and ball joints before I picked up the vehicle. Well, it's May and the coolant loss is gone but I'll continue to keep any eye on the coolant level every month just in case the timing cover starts leaking but I read that problem was on the 97s and not 98s. Got into a habit of checking the engine (coolant, oil level, signs of leaks) every month anyways :)

I would suggest to anyone who feels they might be looking at an intake or head gasket leak to have a used oil analysis done. Cheap and easy to do. Look for unusually high levels of sodium and potassium (coolant), and maybe some higher levels of wear metals (bearings).

That is how I determined my lowers were leaking when I had my 97. :-X22

INTAKE GASKET FAILURE?....I have a 98 E-250 4.2 that the coolant cap was left off the bottle and engine got hot and blew.... Mechanic I know had a new crate motor...He installed it w/ new radiator and ran fine for 1735mi....THEN...it started running rough at idle about 4 blks from the house and after it was parked for about 3 hrs Hydrolocked! ..Antifreeze in one cyl on each side...They tore it down and said the headgaskets blew, that I had overheated it? replaced those and now they called me and front drivers cyl (#4?) is CRACKED! engine junk now... Is this from lower intake failure??? Age of FORD Crate motor was unknown but he had had it for several yrs in storage and didn't know the age/yr....Anyway to tell mfg date? and if it was one that had bad intake gasket? Need someone with good knowledge of this issue (PRO) not amature guesstimate

intake manifold leak v/s head gasket leak
 

hello, i have a similiar problem, but i am trying to determine if it is the intake gasket or the head gasket. there is water in my oil, a lot, and when i add water to the tank it runs out from under the engine. 2000 ford windstar 3.8 v6. any suggestion or opinions would be greatly appreciated.

um.
when you add it it runs right out the motor? is it leakin out from where? timing chain? radiator?

zs for coolant in the oil...I hope your not driving this truck right now?