95 Passport...runs rough...coolant leak...head gasket?

[vworld]

hi, just thought i would run this by everybody... i have a 95 honda passport with 158k (3.2 auto 4x4) it started running rough and then the radiator cracked. so i put a new radiator in it and the new one cracked in the same place on the first test drive. could it be a blown HG putting compression in the radiator? if so, isn't the cap supposed to vent that? 2 bad radiators in a row? pulled the plugs they all look normal except one that looked bran new? did a compression test everything between 185 and 200 psi with one low cylinder at 165 psi? trying to figure out why the radiator cracked twice and why it runs so bad? thanks in advance for the help.

[trooperbc]

where did it crack?

is it the 'plastic' radiator, and it cracked at the top hose? which is most often from overtightening the clamp.

[Ramblin Fever]

Actually, having had to replace your 1st radiator on a '95 is about right, they're typically only good for 7-9yrs. If they don't crack on the outside - plastic, they're usually corroded on the internals anyways by about 9-10yrs.

I too just replaced my OEM radiator at 160k miles on my '97 Rodeo - nothing was visually wrong with it, but I'm big on preventative maintenance and just assumed the internals were worn out anyways.

I went with an all metal radiator, won't do plastic again, for reason already mentioned in regards to overtightening possibilities with the clamps.

At about 151k miles, my truck started running terrible then too. After a long list of replacement parts =

timing belt, timing belt tensioner, idler pulley
waterpump (waterpump croaked at 152k),
fuel filter, air filter, transmission filter, pcv, EGR cleaned
spark plugs,
all new O2 sensors (2 were bad, 2 were on their way out)
radiator, transmission, rear axle flush/changes
3 new driving belts, all new coolant/heater/transmission hoses

I'm sure I may be forgetting something, but it's all been replaced in the last 8k miles or so, and the truck is running like it's brand-new again, I LOVE IT.

I couldn't afford to do it all at once, so I did a little at a time over the course of 5-6k miles, but it's made a world of difference.

Before, mine was running real rough, lost power, and just didn't have the umph it used to.

My truck has original engine, auto transmission, and has not required any internal engine work, and this truck has worked HARD 95% of it's life. But, I'm very adament about keeping the cooling system, especially, up to par.

I.e. what I'm trying to say, is I doubt your headgaskets are an issue. Chances are, it could be a waterpump issue, if your pump is original or over 100k miles, get it out. Also, get yourself a metal radiator.

Keep us posted.

[redbug]

I'm with Ramblin, I doubt it is a head gasket, yes, one cylinder is low, but not super low. If you had a head gasket leak I would expect about 30-60 psi. Do you you have water in the oil? That would possibly tip off a leak. As far as your new radiator, would not be the first time a new radiator was bad.... And yes, pressure should have released out the cap. Did you replace the cap when you replaced the radiator?

Before the radiator broke was it losing water...? If it had a head gasket leak it would pressurize out and also suck water in....

Next radiator start it up without the cap on, you will be able to see if air is pushing out the radiator then without over pressuring it.... Put something over it while it is still cool and see if it is building up pressure... Of course when it gets hot it will pressurize....

If it is the head gasket, I would recommend pulling the engine if you think you are going to do the job yourself.. I have only removed a head on my 95 and I can tell you I wish I had pulled the engine first, probably would have been quicker...

As far as it running rough, that could be caused by the low compression in the one cylinder or possibly a bad injector... ? Plug that is clean may not be getting fuel and is therefor not getting dirty....? Is the one clean plug the cylinder with the low compression...? Although, if water is getting in that cylinder it could be reacting with the carbon and cleaning the plug.......

[Ramblin Fever]

Well one thing for sure that will blow the heads is if the engine ever got hot, that's a possibility.

But, just seems unlikely on a cooling system that's been flushed regularly etc, for the heads to go on these engines. But, it is possible I reckon.