Aftermarket Radiator Pressure Issue?

[ThatOneGuy99]

Anybody have any ideas? Time to replace the radiator and water pump?

 

[Josh P]

I don't like the 1st picture. It does look like you need to deal with the water pump and a replacement radiator. If I had to guess with the 1st picture based on what you describe, I'd think you had a cracked head or bad head gasket.

 

[ThatOneGuy99]

So I looked closely, the line of coolant I saw coming out of the water pump from the gasket wasn't the water pump, it was coming from the timing cover. I was honestly planning to replace the heads with some new cast kings heads, and also new timing parts while I have it all apart. I already ordered the new radiator though. The coolant in the radiator does have a small bit of an oily film on it which I know is a pretty good sign of a head issue.

 

[BKennedy]

The radiator is leaking for sure. The previous owner wasn't completely honest if he said that is a all aluminum radiator.

 

[CDW6212R]

Yeah, replace the radiator and narrow down the other leak too. If it's from the timing cover, that's not a fun job, but much better than doing heads.

 

[ThatOneGuy99]

The radiator is leaking for sure. The previous owner wasn't completely honest if he said that is a all aluminum radiator.

He didn't, he just said "heavy duty three row"

 

[ThatOneGuy99]

Yeah, replace the radiator and narrow down the other leak too. If it's from the timing cover, that's not a fun job, but much better than doing heads.

Can't say it matters much to me either way. I'm more of a person to just do it now even if it is working so I won't have to do it later. I grew up working on old Mercedes diesel engines, I'm assuming this isn't going to be harder than that, but I've been wrong before

 

[BKennedy]

Somebody else with a 2nd gen can chime in here, but if the OP is pulling the timing cover, isn't there a bunch of stuff he should also do?

 

[ThatOneGuy99]

Somebody else with a 2nd gen can chime in here, but if the OP is pulling the timing cover, isn't there a bunch of stuff he should also do?

I just figured timing chain and maybe the camshaft sprocket

 

[Fix4Dirt]

Somebody else with a 2nd gen can chime in here, but if the OP is pulling the timing cover, isn't there a bunch of stuff he should also do?

it being an ohv theres not the stuff like the timing chains in the sohc to do. one could do them preventstively, but i dont hesr of those often. but maybe the ohv guys know more

 

[Onebigbird]

So I pressure tested the system at 25 PSI (it's kinda high I know), I found three leaks.
View attachment 432610
I don't know what this one is, I checked all above and around and there isn't a trail and it wouldn't drip for me.

View attachment 432612
This one started at the front of the block where the water pump meets at the right side and ran down the seam to the oil pan and collected there.

View attachment 432613
This one is leaking like a sieve under pressure.

The brand of radiator is Tong Yang (pretty sure they supply several Asian brands as well as Mopar) but their website doesn't list a part for the explorer so idk what this radiator was meant for.

Is that a rust spot on the first picture? And is rust spot that has gone through the metal?

 

[Turdle]

Freeze plug leak?

 

[DMichaels]

Before you tear into it I’d do a check for a head gasket leak from the top. I just rebuilt a 99 ex sohc. Big back pressure before tear down from a leaking head gasket. There might be extra pressure in your cooling system. You’d want to know about a head gasket before you do anything.

 

[ThatOneGuy99]

Is that a rust spot on the first picture? And is rust spot that has gone through the metal?

This is a California truck so most of the rust is super shallow surface rust or it's just mud/dirt.

 

[Josh P]

Freeze plug leak?

Possible, but with oil film and pressure in the radiator it has other issues too.

 

[94Eddie]

So I looked closely, the line of coolant I saw coming out of the water pump from the gasket wasn't the water pump, it was coming from the timing cover. I was honestly planning to replace the heads with some new cast kings heads, and also new timing parts while I have it all apart. I already ordered the new radiator though. The coolant in the radiator does have a small bit of an oily film on it which I know is a pretty good sign of a head issue.

Have you tested for exhaust gases in the cooling system? This would tell you if there is a head gasket issue.

 

[Turdle]

Oil film could be trans fluid exchange in radiator. We've already determined it's cracked

 

[ThatOneGuy99]

Have you tested for exhaust gases in the cooling system? This would tell you if there is a head gasket issue.

I haven't tested that yet, I'm gonna pick up the kit after work today.

 

[MikeHTally]

I have to add this, I went to pick up the pressure tester and the guy behind the counter told me the 4.0 OHV V6 was one of the worst and most unreliable engines Ford ever made. He then claimed to work at a shop and later on in the conversation asked me if the triton V10 was a diesel. Last time I attempt an intelligent conversation with young AutoZone employees

I had TWO NAPA employees tell me the Hemi in the Ram was 4.7L and tried to sell me a PCV valve for the 4.7 to fit the Hemi.

 

[Mbrooks420]

I typically show up to the auto stores with part numbers, if I don’t order online and just pick up.