water temp in an xflow - what is too high?

[twobone]

Normally she runs around 90 degrees.

 

In slow traffic it moves up to 100-110. Is over 120 a major concern?

 

I have a dry sump and oil cooler so the oil stays cool

[11Budlite]

I have no experience with a xflow, but as a comparison my '64 MGB temp gauge goes up to 230 F (equivalent to 110 C). I don't think I've ever seen any of my LBC's get anywhere near that reading and thankfully I've never had one overheat. The pressure cap in the system is 7 psi so it should raise the boiling point to appr 233 F. I might be a little overly cautious but if I ever saw a reading that high on my MGB I'd start worrying that the 48 year old cast iron cylinder head would crack! I know modern cars probably run much hotter than that but I'd start getting concerned if it started to get close to 110 C. Hopefully some xflow owners will be along to share their experience. What radiator pressure cap are you running in the cooling system?

Edited August 16, 2012 by 11Budlite

[twobone]

not sure the pressure cap spec. I will check it out

 

Thanks for the insights!

[xflow7]

That sounds awfully hot. I've always heard the conventional wisdom with crossflows is basically, the cooler the better and people generally run 71C or 82C thermostats in Sevens. Mine starts running poorly much above 85 or 90.

 

Once you're up around 90C, your fan should probably be on - those are usually on 84C or 88C switches, IIRC. Is it? With the fan on, the temp should come down well below 100, at least.

 

If the fan's not on, then you could have a bad fan switch (has happened to me). Alternatively, there's always the possibility of a faulty temp sender or gauge and the engine's not actually that hot. Check the connection at the sender first of all. I think the single-wire temp senders are basically resistance devices and will reflect a bad connection as a high temperature.

 

Dave

[BruceBowker]

My crossflow stays at around 90 C. Tad higher in heat but not much.Never saw it reach 110.

[bball7754]

There are obviously a few variables (air temp, speed), but my Crossflow is "normally" between 80 and 90. If it's cool out and/or I'm traveling at 45+ mph, it usually stays closer to 80.

 

At a recent track day, air temp was in the low 90's (fahrenheit), and towards the end of a session the engine would be up to 100C.

[Sabbot]

If the gauge on mine is to believed it runs up to 80oC then the fan kicks in. I once accidentally had it running at 2500rpm at a standstill to balance the carbs with the otter switch accidentally disconnected (fan off) and it boiled over with the gauge reading around 120oC - which seems about right for the pressurized system.

[The Stig]

My Crossflow generally just under 90 pretty much all the time. Fan on around 92 or so and brings down nicely. I did have a previous CF and that ran at 100 all day long. Higher than I liked but was fine.

[TheDingo8MyBaby]

Here's the steps I'd take:

 

1. Coolant System Flush & Confirm thermostat opening, check gauge for accuracy (caterham OEM gauges are not stellar)

 

2. Water Wetter

 

3. Cooler Thermostat

 

4. Fan Upgrade.