2.25 petrol overheating

[bugeye88]

Another thing to check is do you have the full fan shroud in place around the fan? If not you may want to install a thermostatic controlled electric auxiliary fan. The "Pusher" type in front of the radiator fits best.

Cheers,
Rob
Bugeye88

[Jdnewberry]

One of the first things I did was add the shroud. Since this issue didn't show up until the weather warmed up, I just assumed the missing shroud was the problem.

My mechanic said that if I was running lean I would feel it in lack of power, but I'm still skeptical. I'm going to order a larger main jet today and see if that does anything. He may be right, but for $5 I can find out for sure.

[SafeAirOne]

Are the fins in your radiator damaged or clogged up with bugs/debris/mud? Is there anything blocking the flow of ram air into the radiator?

[Jdnewberry]

It's pristine. The radiator is only 6-7 months old and has never been off road, so no mud. No bugs either. I have already been that route.

[SafeAirOne]

You're not making this easy, are you?


I don't know about the "too much radiator flow" theory. Hundreds of thousands of these vehicles haven't had a problem with the same setup; What makes yours different? If your radiator is a stock radiator, and your water pump isn't on steroids and the coolant is going where it's supposed to, then I think the only thing left that could have that much effect on the coolant temp is a head gasket issue or damaged head/block as Ike listed before.

What are your engine-hot compression numbers?

[o2batsea]

Anything over about 25-30 MPH the engine fan stops doing anything. Prolly the 4 core is keeping the airflow below optimum. That is, the wall of air that you push isn't getting thru the opening, and the engine fan, having lost effectiveness, isn't helping.
It may be counterintuitive, but try removing the fan shroud and test driving it.

[Jdnewberry]

The compression is a little off, but not extremely bad. Cyl 1 is 150, 2 is 140, 3 is 170, 4 is 160.

I don't think it's the gasket since I'm not seeing the typical signs, but I haven't ruled it out for sure. I also can't imagine that's it's the cooling system with as much as I've replaced and inspected. I don't think it's the head, because that was just worked over by a well respected shop.

A problem in the block is possible I suppose, but unlikely as the engine only has 27000 miles. I question the fuel/air ratio and have ordered some larger jets, but could it also be a weak fuel pump? The inline fuel filter never fills more than 1/3 full, but the engine never cuts out like its starved for fuel. I don't know that a weak pump could cause a lean condition, but I'm grasping at straws.

[Jdnewberry]

Anything over about 25-30 MPH the engine fan stops doing anything. Prolly the 4 core is keeping the airflow below optimum. That is, the wall of air that you push isn't getting thru the opening, and the engine fan, having lost effectiveness, isn't helping.
It may be counterintuitive, but try removing the fan shroud and test driving it.

I'll try that this afternoon. The shroud was one of the first things I tried when it started running warm, but it only made a difference at idle. I have found more things that have lowered the temp, so I suppose the shroud may be in the way. It's definitely worth a try.

[Jdnewberry]

Re-jetting the carburetor and removing the shroud didn't help. I'm going to try the head gasket just in case. Any thoughts on the type of gasket? Copper or composite?

[SafeAirOne]

If it were me and a composite gasket was available, I'd be using that. No re-torquing required and they're designed to bond to the block and head once heat and pressure is applied. Need CLEAN, flat surfaces, though.

[Jdnewberry]

If it were me and a composite gasket was available, I'd be using that. No re-torquing required and they're designed to bond to the block and head once heat and pressure is applied. Need CLEAN, flat surfaces, though.

That's what I was thinking. The cleaning is what I'm dreading, though. It has a composite right now and I hate the thought of scraping the old gasket.

[Jdnewberry]

Sorry it's been a while since I've updated the thread. Been a little busy lately!

I have determined it's not the head gasket, so my thought is that it's running lean. I increased the main jet in the carb, but no change. If it is the fuel, then it's most likely somewhere between the tank and the pump.

I did notice something today, though. I have one of those clear inline filters between the pump and carb and it had bubbles being pumped into it. If a fuel pump is failing, could it draw air? I have checked the fuel line connections and even added hylomar, so I doubt there is a leak in the lines, but anything is possible. What are the odds that this has been my problem all along?

http://youtu.be/okFqxo9kMXk

[SafeAirOne]

http://youtu.be/okFqxo9kMXk#sthash.4MqRcGHg.dpuf

I don't know that that's your problem, but it ain't right.

[Jdnewberry]

Well, I'm going to try a new fuel
Pump and see what happens!

[Jdnewberry]

I fitted a new mechanical fuel pump and also an electric pump next to the fuel tank. Still overheating, but I do have more power at highway speeds. I suppose that's a bonus, but I'm still trying to figure this out. Any more ideas?