In the current bout of high temps affecting much of the US, including my area around DC which tomorrow will creep up toward but hopefully not hit 100, has anyone found if our X308s handle heavy traffic in very high temps well? I remember having to pull over at a Jag event years ago in my X300 which, while idling along at a crawl, went into vapor lock. I popped the hood and got some towels soaked in cold water to lay across the fuel rail. I had the path into the winery nearly blocked until I could restart the car.

I know the previous owners took very good care of the 308, but in three year’s I’ve not replaced any hoses and I don’t know when they might have. I’m a more than a little concerned about both vapor lock creeping along and the engine overheating as my drive to and from band practice is an hour to 75 minutes in heavy DC Beltway traffic. I’m going to take my thoroughly expendable Prius instead, but I’m trolling here for longer-term guidance.

With thanks, and please be careful and stay cool.

 

If your thermostat housing is plastic, replace with an aluminum housing as well as replacing the thermostat. Make sure both of your cooling fans are properly working. If you have access to a strong air compressor, (or strong leaf blower) use a blow gun with a long wand attachment and blow out the radiator and condenser towards the front of the car so any lodged debris will get cleared from said radiators.

One last thought... when you run your A/C, do you ever notice if your high speed cooling fans come on and then switch to low speed after 20-30 seconds? If you do, you may have a problem with your A/C pressure being too high. When that pressure gets too high, that condenser in front of the radiator can get really hot and transfer heat right onto the radiator. Just a thought.

 

All good advice and thanks. It's an '03 so I think the thermostat housing is aluminum but will check. I'll see what I can do about extracting/blowing out any debris. I have not noticed any issue with the fans, but it's something I'll also keep an eye/ear out for.

I sure don't want to blow a hose or have vapor lock on 495 at rush hour coming home from practice and ruin everyone else's commute, not to mention exposing my instrument to that kind of heat.

Cheers, and I wish all a hassle free, relatively cool weekend.

 

There is sufficient cooling capacity in the x308 to handle ambient temperatures of 100f/37c.
As long as everything is in proper working order, they won’t overheat or vapor lock.

 

vapor lock should not be a concern with fuel at roughly 40psi in the rail at idle.

 

I took wifey to a concert in Hershey, PA, in August of '15. It was pretty hot and traffic getting into the parking lot was worse than anything that I had seen on the 495. AC was running the whole time and it took about two hours to get parked. No problems, but that was before I installed JW's Real Gauge ECT mod. If you're worried about overheating, get that mod; it squeals at around 235F or so, well before the magic temp to blow a head gasket. But, it will scare you with how high the EC temp can really get to.

In a band? Are you the lead singer ???

 

Just because it’s an 03’ VP, that doesn’t mean it has an aluminum thermostat housing. The only way it would’ve been an aluminum thermostat housing from the factory is if it was supercharged. Seeing that you bought it with low mileage, it’s entirely possible that it could be the original plastic housing.

 

Thanks to all for restoring my faith in British engineering, aka cooling capacity of the 4.0 engine.

To A2B: the reason I believe, rightly or wrongly, that I have an aluminum thermostat housing, is that when I tapped it with a screwdriver, it sounded metallic. However, it is black, which might be more indicative of a plastic housing. I was unaware the plastic unit was used throughout the X308 run except for the XJRs getting aluminum. Another reason this board — and some of its more knowledgeable denizens — hold a wealth of knowledge.

Hispeed: my primary contribution to the field of music is to refrain from singing. My secondary contribution is playing mandolin in a group that does ‘60s and ‘70s folk- and country-rock. Given our advancing age, hair color and the fact we cover some Grateful Dead material, we bill ourselves as Touch of Grey. We play that tune, but it isn’t a regular on our set lists. My vapor lock question was driven by the fact I live in Annandale, Va., around the DC Beltway about 35-40 miles from where the band is based in far northwest Montgomery Co., i.e. Poolesville, Md., near what used to be Whites Ferry many folks from Washington Center used to commute to work. It’s now idled by a dispute about access to the landing on the VA side.

I’m attaching two photos of what I think is the thermostat housing if someone can say — yeah, that’s the @#$%^& plastic one that should be changed out at some point (I presume.)

 

The “02” indicates that it’s most likely the original plastic.

I would definitely start by upgrading to the aluminum thermostat housing and a new oem thermostat and gasket. You could first use a live data scan tool just to make absolutely sure that your gauge isn’t reading improperly so you know what the temperature is as your driving. 95*C (203*F) is where it should be at but, in my opinion if it reaches 100*C (212*F) and I would turn the A/C off and heater on full hot and max air speed.

 

Good catch, sir, and many thanks. That thing is so old it can buy gin at the liquor store legally. If I recall, the final assembly date on this VDP was July ‘02. I had some Volvos along the way in which I had to open the windows and turn on the heat full bore to get the temp to come down. That’s been a long while.

 

Water boils at 212*F: but pressurization and coolant raise the boiling point much higher. As long as the fans are working, the thermostat is opening, and the cross pipe is solid, the car should cool. To be safe, as noted, use an OBD reader that can give live readout of the engine temperature.

Changing the thermostat tower, the TST, the water pump, belt, and crossover pipe and stubby, along with renewed coolant should keep the car cooling until Fall . . .

As for Volvos . . . I remember climbing the mountains North of LA on I 5 in 1972; Volvo had just been rebuilt after an accident and car was pinging its *** off under load. Down in San Diego, sent wife to a repair shop to have antifreeze added . . . no more pinging and running for full power (as slow as it was for a 1970 Volvo!).

 

Hispeed: my primary contribution to the field of music is to refrain from singing. My secondary contribution is playing mandolin in a group that does ‘60s and ‘70s folk- and country-rock. Given our advancing age, hair color and the fact we cover some Grateful Dead material, we bill ourselves as Touch of Grey. We play that tune, but it isn’t a regular on our set lists. My vapor lock question was driven by the fact I live in Annandale, Va., around the DC Beltway about 35-40 miles from where the band is based in far northwest Montgomery Co., i.e. Poolesville, Md., near what used to be Whites Ferry many folks from Washington Center used to commute to work. It’s now idled by a dispute about access to the landing on the VA side.

Hmmm, have you tried the three beers trick? My singing is always a lot more better after three, and I'm a rock star with four to six. Unfortunately, I kind of forget how to work the recorder at that point, or I would post some examples. And, I always end my sessions with "Ripple." The only problem that I see is getting back home after practice; hopefully the host has a bathtub or something where you can sleep-off the beers. Another "And:" yeah, that’s the @#$%^& plastic one that should be changed out ASAP.

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