DodgeIntrepid.Net Forums banner
1 - 9 of 9 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter · #1 ·
I have a 2000 Intrepid 3.2 that I recently discovered has coolant in the oil. Car has 89,xxx miles and has been babied it's entire life (my grandparents bought it new), never overheated, etc.

I haven't driven the car in several months because of tie rod issues so that car has been sitting. But last time I was driving regularly, I didn't notice anything that would suggest a blown head gasket. I DID replace the radiator about a year ago, and it seems like ever since I have had problems with the transmission cooling lines leaking. I read another post from a few years ago about oil cooling lines causing coolant mixing issues. If I remember correctly, they are on the passenger side of the car, which is the side I don't see any external leaks from. I only see them on the driver's side. I understand that the leaks are internal to cause those issues, but I guess my point is I didn't overtighten or do anything excessive when hooking them up.

Is it possible that the cooling lines are causing mixing issues on a new radiator? I honestly don't remember the brand. I just don't see how "suddenly" the car has a blown head gasket, crack, etc. I am going to use my pressure tester to check for pressure loss tomorrow. I'm just at a loss between a sudden head gasket failure or brand new radiator failure.

Does anyone have any experience or thoughts on the oil cooling lines causing these issues on a brand new radiator? How common are head gasket issues on 3.2's?

Thanks for any advice.
 

·
Premium Member
Joined
·
18,389 Posts
Yes - transmission fluid cooling lines are on the driver's side of the radiator, engine oil cooling lines are on the passenger side.

If the transmission cooling lines are leaking where they plug into the radiator barb fittings, the hose clamps at the barb fittings are a little loose (a common problem as the hose rubber takes a set, and the screw type clamps are very poor at maintaining the sealing of hose to barb because they have bumps on their ID that applies very uneven pressure all around the Hose OD), the hoses may cut thru from the clamp pressure at the barbs (unlikely), or the connection of the barb fittings into the radiator are loosened (they could be attached to the radiator by a large nut and sealing washer that has loosened). Regular screw-type hose clamps are poor design for those hoses even though that's what comes from the factory. I strongly suggest replacing the screw-type hose clamps with fuel injection-type hose clamps - they put very even pressure all around the diameter of the hoses so they seal well and eliminate the possibility of the batbs cutting thru the hoses unless severely overtightened - and probably not even then. If the ID of the hoses are chewed up from the barbs, you likely have just enough extra length on the hose ends to snip the damaged part off and reconnect with undamaged ID and the fuel injection hose clamps.

The oil cooler line inside the new radiator likely has a leak in it - so coolant is leaking into the engine oil that way. It has happened on a few of these cars, and aftermarket radiators can be very hit-and-miss.

Fuel injector hose clamps - they apply very even pressure all the way around the hose OD for good sealing with no cut-thru - get the right size to fit the hose at most auto parts stores:
Automotive lighting Auto part Jewellery Electric blue Event
 

·
Registered
Joined
·
12 Posts
Discussion Starter · #3 ·
Yes - transmission fluid cooling lines are on the driver's side of the radiator, engine oil cooling lines are on the passenger side.

If the transmission cooling lines are leaking where they plug into the radiator barb fittings, the hose clamps at the barb fittings are a little loose (a common problem as the hose rubber takes a set, and the screw type clamps are very poor at maintaining the sealing of hose to barb because they have bumps on their ID that applies very uneven pressure all around the Hose OD), the hoses may cut thru from the clamp pressure at the barbs (unlikely), or the connection of the barb fittings into the radiator are loosened (they could be attached to the radiator by a large nut and sealing washer that has loosened). Regular screw-type hose clamps are poor design for those hoses even though that's what comes from the factory. I strongly suggest replacing the screw-type hose clamps with fuel injection-type hose clamps - they put very even pressure all around the diameter of the hoses so they seal well and eliminate the possibility of the batbs cutting thru the hoses unless severely overtightened - and probably not even then. If the ID of the hoses are chewed up from the barbs, you likely have just enough extra length on the hose ends to snip the damaged part off and reconnect with undamaged ID and the fuel injection hose clamps.

The oil cooler line inside the new radiator likely has a leak in it - so coolant is leaking into the engine oil that way. It has happened on a few of these cars, and aftermarket radiators can be very hit-and-miss.

Fuel injector hose clamps - they apply very even pressure all the way around the hose OD for good sealing with no cut-thru - get the right size to fit the hose at most auto parts stores:
View attachment 42357
Thanks. I've never seen those clamps before, but I'm used to the spring style and Corbin clamps on the old stuff.

You guys have experienced oil cooler failures on new replacement radiators? I'm not sure why I'm these cars they "cool" through the radiator. I have a 440 police package Monaco and a police package Diplomat and the oil coolers on those use a separate external cooler.

So I guess my question now is, if I'm planning on removing the oil cooling lines and plugging them off (and plugging where they attach to the radiator), if the oil cooler inside the radiator is cracked/leaking, will that cause any issues even with the oil lines plugged? I really don't want to have to replace the radiator as it's not leaking antifreeze anywhere.

Thanks again
 

·
Premium Member
Joined
·
18,389 Posts
Aftermarket quality in general is all over the place, and some real crap has been seen by many here, particularly in radiators. A few experienced that internal coolant-oil leak, but I don't know what percentage of those were in factory-original radiators vs. aftermarket radiators either right out of the box or after some time in service. I can't guarantee that the oil cooler in your new radiator is your problem, but it seems likely in that that is a failure in general that has been experienced by a few owners on this forum, and as you pointed out, the advent of the problem coincided with the installation of the new radiator.

More than a few owners have uninstalled the oil cooler plumbing without problem. Chrysler itself decontented it in the middle of LH platform production (2002), likely as a cost-cutting measure.

Removing those lines would not cause any problems. If there were no hole or crack in the line inside the radiator, you would not need to plug the ports (I and many others left the ports unplugged without problem), but if there is in fact a hole/crack, if you don't plug the ports, you would have coolant leaking out at some, at this point, unknown rate.

If you're curious to determine if there really is a leak in the radiator, you could leave those ports unplugged and see if you get coolant leakage from them, and then plug them later. :)

Here is some advice on disabling the oil cooler: Remove the entirety of both the supply and return lines starting at the supply port from the hole in the block (next to the oil filter), which would involve the swivel joint tee fitting that the oil pressure switch is screwed into. That has the extra benefit of getting rid of the tee, which is known to develop serious leaks (in its swivel joint). You would remove the oil pressure switch and the tee, and screw the oil pressure switch directly into the engine block where the tee screws into now. Then remove the line from there to the radiator.

(You might want to take the opportunity to replace the oil pressure switch at this time since they are prone to developing leaks and also getting out of calibration (turning the oil light on when oil pressure is actually in spec). This is a part that you definitely want to get from a dealer as the aftermarkets are very often out of calibration right out of the box. You should pick up the special socket for the pressure switch at the parts store - $10-$20 - don't shoot me, I'm just the messenger - a standard hex socket won't fit. Improvising with pliers or whatever risks damaging the new switch when installing.)

On the return side, that line goes directly from the radiator port to threaded hole in the side of the oil pan. There is a spring and ball flow restrictor(?) at the oil pan end. The guts of that restrictor (ball and spring) have been found rolling around in the bottom of the oil pan by more than one owner. Them being in the oil pan itself is not a problem, but whatever purpose the restrictor serves (perhaps to keep the line filled with oil when the engine is off?) is no longer being performed at that point.

As you can see, the design of that cooler was a mess and potentially creates more problems than it was intended to solve, which is another reason Chrysler (in production) and many owners (after the fact) removed the plumbing. Probably the decontenting of the oil cooler lines by owners was triggered by the tee leaking oil, and Chrysler wanted quite a bit (IIRC, well over $100) just for the part, and fairly early on, they become completely unavailable as a replacement part, with no way to repair the tee.

The return port in the oil pan is a standard NPT female tapered pipe thread - so just get a standard 3/8" pipe plug at Home Depot or Lowes to plug that. It's not a pressurized connection, but might as well put a little RTV on the plug thread.

There is one bracket in mid span of the cooler lines that is attached to the engine with one or 2 of the oil pan bolts. So with little extra effort, you can do a very clean uninstall of both cooler lines in their entirety.
 

·
Registered
Joined
·
12 Posts
Discussion Starter · #5 ·
Thanks a lot. What you said about not putting plugs in the radiator where the oil cooling lines go gives me an idea. If I unhook the cooling lines, put my pressure tester on the expansion tank and leave it pressurized for awhile, if that's where the mixing is happening I should see coolant coming out of the ports and hopefully rule out something more serious.
 

·
Premium Member
Joined
·
18,389 Posts
Thanks a lot. What you said about not putting plugs in the radiator where the oil cooling lines go gives me an idea. If I unhook the cooling lines, put my pressure tester on the expansion tank and leave it pressurized for awhile, if that's where the mixing is happening I should see coolant coming out of the ports and hopefully rule out something more serious.
👍
 

·
Premium Member
Joined
·
18,389 Posts
"Thanks. I've never seen those clamps before, but I'm used to the spring style and Corbin clamps on the old stuff."

Actually, a Corbin clamp might be a good choice for the transmission cooler lines because they maintain constant spring pressure around the hose ID - important for softer rubber that creeps (takes a compression set) over time.

Of the two types of Corbin clamps (see below), because of the barb fittings, I think the type on the right would be a better choice for those transmission cooler lines - YMMV. The Corbins have a fairly narrow range of diameter to maintain good pressure on the hose OD, so they have to be sized carefully for the effective hose OD after installed on the fitting, but when sized right (and allowing for some compression set), they work great. I don't think the transmission fluid supply hose pressure is too much for them not to leak - needs to be verified after the fact:
Rectangle Font Auto part Metal Fashion accessory


A lot of people don't like the Corbins for coolant hoses because they can be harder to work with, but I use them whenever possible because they maintain a constant, even all-the-way-around pressure on the hose even after compression set. A lot of people throw the factory Corbin clamps away and replace with screw clamps - I do the exact opposite on my cars. You just need a decent $25-$40 cable-type tool to work with them (don't cheap out on the tool, and the non-cable pliers-type can't get into tight spots like the cable type can) - that's the key to taming them.

An example of a decent cable-type Corbin hose clamp tool:

 

·
Registered
Joined
·
12 Posts
Discussion Starter · #8 ·
Update

So I've been incredibly busy and never found any time to come back and update the threads I had going with my car....

I could not find any signs of head gasket issues or anything else that would suggest coolant entering the crankcase. I put a pressure tester on the cap, built it up to 16lbs and let it sit for hours (literally bush hogged for 3 hours and came back to check it) and nothing changed. This was with the cooler lines disconnected from the radiator to see if the oil cooler was leaking as a possible contamination source. Everything normal.

The car was being used only for EXTREMELY short trips the entire winter due to the tie rod issues (I have since fixed). I mean several times a week the car would go from my house/shop to the end of the driveway or to my parents who are my neighbors. I think the numerous and constant short trips, humidity/moisture (TN winters) just accumulated a lot of moisture inside the engine. We're talking months of less than 5 minute runs during cold, wet weather.

I did eliminate the oil cooler lines, new OEM oil pressure sending unit as recommended, and plugged the radiator where the lines connected just in case the oil cooler developed a crack at any point.

The car has been running great. It's back to being my "local daily driver" as I commute too far to punish it with racking up high miles.
 

·
Premium Member
Joined
·
18,389 Posts
Yeah, those short cold drives will build up the condensation - really hard on the exhaust system too.

Hot weather for bush bogging!
 
1 - 9 of 9 Posts
Top