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Is it a bad idea to buy a higher pressure radiator cap?

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230F sounds awfully high. (cue broken record) Suggest checking temperature adjacent to the pickup with a couple of thermometers. My gauge used to read around 25 degrees high.

I removed the t-stat housing and t-stat and watched the temp on the thermometers vs that on the gauge. Then moved the gauge pointer to correspond to my other thermometers.
 
Thanks Steve for the help.

The only time the car got hot was on my first drive away from Russ Thompson's. It was Friday before the 4th of July and was probably not a good day to be on the road. But I needed to get the car from Northridge to Redlands, and my options are somewhat limited. Anyway, when all 4 freeway lanes merged onto 2 lanes of an interchange, the freeway just stopped. Russ had advised me to get the car off the road if it hit 212, but when it hit this temperature, there was physically no where to move the car. It blew past 212 quickly and my attention changed to just getting the car some movement. I stopped looking at the gauge and just had to focus on driving. The rear view out of a BJ8 is poor and my fender mirror was midadjusted, so doing safe lane changes was hard. Also, the engine had stalled a couple of times because of the high engine compartment temperatures. Basically, I don't know if it hit 220 or 225 or 230, but regardless, it was rather stressful and I cannot imagine my Mom dealing with all that simultaneously.

Regarding the accuracy of the temperature gauge, it unfortunately is correctly measuring the temperature in that area of the block (as verified with a Fluke IR thermometer). When the gauge read 212 at idle later in the day, I was able to measure 210 by pointing the IR thermometer directly at the temp gauge location on the engine. The hot coolant hose and hot part of the radiator was 205.

One random observation (of probably no value) which surprised me is the air flow direction at the exit of the Derale Flex Fan that Russ installed. When starting the car one day with the engine compartment open, I was really surprised how the fan sends the air out in a radial direction. It didn't seem like it was deflecting off the engine or anything. I just think that type of fans pulls air in along the fan's shaft axis, but pushing it out radially. I have never observed that first hand, but it really supports the efforts discussed here on reducing recirculation of warmed air back over to the front side of the radiator.
 
Just one more quick note. With all my time on the road over the past couple of weeks, it gave me lots of time to ponder other solutions to the overheating issues of Healeys (thus this thread). One other solution I considered was some sort of water misting system which you could use in "emergency" situations to add additional cooling. I soundly rejected this idea as totally impractical and not worth the hassle.

Anyway, I was amused just now to see that Hayden makes that exact product:
https://www.haydenauto.com/Featured Products-Radiator Mist System/Content.aspx

Don't worry, I won't put this on a Healey.
 
Re: potential leaking from the water pump question. When I got my 100 it did have a leak around the water pump seal and the pump looked pretty new. I thought it might be a pressure problem but testing showed not the case. A knowledgeable buddy told me that I needed to spin the new replacement pump at a high rpm for several minutes before installing to "seat" the seal. I set up a rig on my drill press to do that. The new pump (from Moss) does not leak. Assuming the PO did not take that step.
 
MikeAH100M said:
Re: potential leaking from the water pump question. When I got my 100 it did have a leak around the water pump seal and the pump looked pretty new. I thought it might be a pressure problem but testing showed not the case. A knowledgeable buddy told me that I needed to spin the new replacement pump at a high rpm for several minutes before installing to "seat" the seal. I set up a rig on my drill press to do that. The new pump (from Moss) does not leak. Assuming the PO did not take that step.
Click to expand...

Yes!
it can be a pressure problem so do not :

buy a higher pressure radiator cap
 
shortsguy1 said:
Just one more quick note. With all my time on the road over the past couple of weeks, it gave me lots of time to ponder other solutions to the overheating issues of Healeys (thus this thread). One other solution I considered was some sort of water misting system which you could use in "emergency" situations to add additional cooling. I soundly rejected this idea as totally impractical and not worth the hassle.

Anyway, I was amused just now to see that Hayden makes that exact product:
https://www.haydenauto.com/Featured Products-Radiator Mist System/Content.aspx

Don't worry, I won't put this on a Healey.
Click to expand...

I knew a guy years ago who installed a windshield washer pump in front of his radiator for long climbs up the Baker Grade pulling his boat. He said it worked great. Didn't use it all the time, though.

IMO some of these issues are due to a brand-new engine.
 
shortsguy1 said:
Just one more quick note. With all my time on the road over the past couple of weeks, it gave me lots of time to ponder other solutions to the overheating issues of Healeys (thus this thread). One other solution I considered was some sort of water misting system which you could use in "emergency" situations to add additional cooling. I soundly rejected this idea as totally impractical and not worth the hassle.

Anyway, I was amused just now to see that Hayden makes that exact product:
https://www.haydenauto.com/Featured Products-Radiator Mist System/Content.aspx

Don't worry, I won't put this on a Healey.
Click to expand...

Why? Won't it fit???
 
It will be interesting to see if the running temperature of the car changes as the engine wears in. I think the cheapest and easiest solution is to just avoid true gridlock with an App like Waze. The car's temp is fine in modest congestion and shows no temperature issues even driving up steep grades at speed on a hot day.

Does anyone use the heater to cool the engine a little more in emergency situations? I haven't used the heater yet, so I don't have a sense if it provides much capacity. The electric blower for the heating system doesn't seem particularly powerful in this car.

Keoke, regarding that radiator mister, it just seems like such a brute force solution to what is not yet a critical issue. If using a 10 psi cap is a bandaid/bodge, putting that bulky system on a small sports car seems rather inelegant. I want my engine compartment to appear somewhat original in appearance.

Anyway, regarding my original question, you have all helped me think this through. 7 psi it is. Thank you.
 
"Does anyone use the heater to cool the engine a little more in emergency situations? I haven't used the heater yet, so I don't have a sense if it provides much capacity."

Don't know about a Healey in particular, but back in the day ('70's, '80's), I was young and poor, and traveled to from SF Bay Area to Northern NM and back, many times, to see my mom. During the hot months, climbing from Bakersfield to Mojave, and then climbing from Kingman to Flagstaff could be a challenge. I would almost always have to turn off the AC (on cars that actually had it!), and then run the heater at full speed, and maybe slow down a bit to make up the long passes w/o overheating. So, in my experience, the heater core does add enough surface area to the radiator to help keep from boiling over, but YMYV.

I can't see how it would hurt to try it if the temp starts to creep up. Or, try it under steady load, at a steady speed, and see if the temp drops a bit.

When is the last time (except at shows) has anybody seen a Desert Water Bag hanging on the front of a car?

Jim
 
OH Yeah Jim:

Usually on long up hill climbs turning on the heater is a method of reducing Healey engine heat for a short time.
Coming up Highway 89 in AZ from Phoenix will sure ask you to do just that TOO.:encouragement:
 
shortsguy1 said:
Does anyone use the heater to cool the engine a little more in emergency situations? I haven't used the heater yet, so I don't have a sense if it provides much capacity. The electric blower for the heating system doesn't seem particularly powerful in this car.
Click to expand...

I used to refer to my heater (which was useless even in mild NC winters) as the "auxiliary engine cooler", since that's about all I was using it for. It did provide a little bit of additional engine cooling for a short time, such as getting through the sudden aggravation of road construction or heavy traffic if it didn't last too long. As I said, re-coring the radiator with a modern core and installing a sleeved thermostat solved all of my engine heat problems. The heater is still useless in winter, except to help de-fog the windscreen.
 
shortsguy1 said:
Just to answer my own question that I posed a few days ago, according to Anderson and Moment (in the Austin Healey Restoration Guide, p. 152), during BJ8 production, the 7 psi cap was replaced by a 10 psi cap. It isn't clear to me if all BJ8s came with 10 psi, or if it was in the middle of production.
Click to expand...

The parts manual shows only two part numbers for the radiator cap, and no "change point" is given. The ARH 1542 is a 7 psi cap, but I have been unable in an internet search to identify the pressure rating of the ARH 1662 cap. The change in part number may indicate a change in pressure rating, or it may indicate something else. Without the specs for the part numbers, it isn't possible to tell.
 
A few years ago I was pulling with a full load in my BJ8 coming out of Death Valley up the east side of the Panamint Mountains range. The temp in the shade in DV was 115degF. There were lots of cars--and a tour bus--on the side of the road with their bonnets up. We hit 212 on the temp gauge, and it was moving up until we turned the heater on full blast, and that's where the gauge stayed for the rest of the climb. Lemme tell ya, life in a BJ8 on a 115deg day with the heater on full blast was, er, an experience. We had a spray bottle we used as a mister--for us, not the car--and that did help a lot.
 
We had a spray bottle we used as a mister--for us, not the car--and that did help keep us cool a lot.

Yeah-:congratulatory:
That is a standard Healey cockpit air conditioner---Bob---:applause:
 
Not to open up a whole new can of worms, but I wonder if Evans Coolant would be a good solution (search Evans for a bunch of threads on it) rather than a higher pressure cap if all you're looking for is a few extra degrees of protection. You might also consider Water Wetter or equivalent, although results are mixed, but it's cheap enough for an experiment. Again, you're not going to fix a major cooling problem with it, but it may give you a bigger safety zone.

And Steve, I searched on the alternative cap # and found they used it as a replacement cap on bugeyes when the original stocks expired. I'm used to bugeyes coming with 7 psi, so I'm making a guess it's a 7 also, but who knows for sure.
 
HealeyRick said:
Not to open up a whole new can of worms, but I wonder if Evans Coolant would be a good solution... You might also consider Water Wetter or equivalent, although results are mixed.
Click to expand...

Both are just modern varieties of snake oil, so to speak.
I would not waste any money on them.
 
Re: coolant/water wetter and other heroic solutions:

Andrew (Shortsguy) may not have a problem at all. He was stuck in bad traffic in hot weather with a brand-new rebuilt engine. Let's see how hot it runs with a couple thousand miles on it.
 
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