TR2/3/3A Coolant spit out of overflow

[mgedit]

Took car out for about a 20 mile run last night and all was well, but still less than 200 miles since restoration so still sorting things out. Having read a number of threads about overheating I have been keeping an eye on temperature gauge. Was running at about half way on gauge. When I got home, stopped in driveway to open garage door. As I returned to car noticed large puddle underneath and temp gauge had maxed out (engine shut off). All hoses seem OK. Looks like coolant was forced out overflow hose onto ground. Have new 4 lb rad cap and running 50-50 antifreeze water mix. What are the most likely causes of symptoms? What things should I check in order of most likely causes? Cheers, Mike

 

[59diamond]

Hi Mike,
I had a recent problem with a leak. the bottom radiator hose clamp on my 60 Bugeye was loose. After tightening that I still had a leak. it turned out that my bypass hose was also cracked and leaking. With the help of Bill M the bypass hose was replaced and now all is well. What I did notice when I had the leaks is that it didn't leak as much or at all when the motor was running, because I believe the water was circulating. When I turned the motor off is when the leak was at it's most. I believe that right after you shut off the motor the system is still presureized and that is when the water really comes out of any loose hose or a hose with a hole in it. My bypass hose looked fine when you just looked at it but when Bill M took it off and squezzed it you could see that it was worn and kinda rotten. Hope this helps.

 

[sp53]

I would say that maybe trapped air still because of the low miles, but the pinning of the gauge suggests otherwise. Did you let it run with the cap off to let the air come out easier? Just to be safe I would pull the valve cover to look for water and then I would also look at the thermostat to make sure it is in correct and working. Maybe the head is loose also.

 

[CJD]

Mine spewed when new, till I realized I couldn't fill the radiator all the way to the top. It has to have a head of air for expansion.

I don't know about the gage pegging. Idling is where these are marginal for cooling. Mine is good for about 10 minutes idling in the summer, or it will overheat. Driving above 30mph for about 2 minutes brings the temp right back down...showing that airflow is the problem.

Another quirk I've noticed with these is that if I sit in the car for a minute or two after shutting it down hot, I can feel the coolant boiling. It feels like a gentle rumble, stopping for about 10 seconds, and then rumbling for 5 seconds or so. The temp always goes up after shutdown. So, if I shutdown with the temp at 185 degrees, it'll rumble for about 10 minutes, and the gage creeps up to about 200. If I didn't have the head of air in the header, I'm sure it would spew every time after shutdown.

 

[Geo Hahn]

I fill the radiator to where I can just see some coolant in the bottom of the neck. Much more than that and it will puke out the excess.

Normal for an engine to get much hotter after you switch it off and heat soaks into the now uncirculating coolant.

 

[mgedit]

Thanks to everyone for sharing your experiences. Will double check fluid level. Maybe it just self levelled for me

Cheers, Mike

 

[charleyf]

Mike,
as you have a new system, do you have the correct radiator cap? My TR3 needed a deeper radiator cap than the standard ones.
Charley

 

[mgedit]

Hi Charley. I purchased cap from TRF and would think it is correct. How deep is your deeper one? How would one check which one is needed. Cheers, Mike

 

[TR3driver]

As noted, sounds like you just had it overfilled and it self-corrected. Also normal for temp gauge to rise immediately after being parked; although I wouldn't expect it to 'peg' unless you had been driving really hard and shut if off suddenly (like going up a grade at freeway speeds and then stopping at the top).

Look into the radiator neck and see the inner seat where the plunger from the cap sits. Measure from that seat to the top of the neck. It should be about 1", meaning you need the original "long reach" cap. If it is only about 3/4", then you need a more common "short reach" cap.

Using a short cap in a long neck just means it won't seal. But a long cap in a short neck will basically never open, causing the pressure to rise until something gives (usually the upper radiator hose).

 

[mgedit]

Thanks for the explanation Randall. Will have a look tomorrow. Would like to get sorted out by the weekend as we have our local club's 25th anniversary drive this coming weekend and my six is under the weather too! Cheers, Mike

 

[BillyB62]

Same deal here - every now and then I top off the coolant just to have it spit out the overflow after the first ride. Freaks my wife out a little, but I know its "normal". Much like Geo, the coolant is best in my car just about when I can see if at the bottom of the neck.

 

[TR3driver]

The downside of that is that it makes it harder to tell when you've got a small leak, especially an intermittent compression leak (which I've had a lot of trouble with in the past). I finally got annoyed enough to add a coolant recovery bottle from a later Triumph:


Not the most accessible location, but unlikely to be noticed by the casual observer, either.

 

[BillyB62]

Randall, where did you put yours? I've been toying with the idea for a while and I'll have my apron off soon to put Mark Macy's fan on (and replace the radiator). It looks like you were going to post a picture in your post above, but it doesn't show for me.

 

[Geo Hahn]

I added one on my TR4 (same spot and same bottle Randall shows) and it works fine -- but on the TR3A I could not get the radiator cap to draw coolant back in on cool down.

I'm guessing that I have the wrong sort of cap for this but the choices available in the deep (1") TR3A cap are limited -- not sure where to get what it takes.

Also, FWIW - here is the pic Randall posted of his (thumbnail and link worked for me):

 

[TR3driver]

Oh, yeah. I forgot to mention that part. My previous attempts with the long reach cap (on my previous TR3A) failed as well, even after adding a rubber gasket between the cap & upper part of the neck. It seemed like the rivet through the center was leaking air back into the overflow area (although it is also possible I had a compression leak at the time). So this time around I had the radiator shop replace the neck with a short reach version. Don't recall the cost, but it was pretty cheap compared to the other work. As an added bonus, I can now use a Stant "Lev-R-Vent" cap with the lever to release pressure into the bottle.

 

[mgedit]

Checked my cap and it is the long-reach 1 inch variety that matches rad. Fluid level is now just visible in neck. Can just touch with the tip of my finger. Will try another run with container of water along for ride and see what happens. Cheers, Mike

 

[Geo Hahn]

You can add a catch bottle (not a recovery bottle) for your test ride, possibly just slip a water bottle over the end of the overflow tube. This will let you know for sure if there is any coolant pushed out & exactly how much.

But now that the level is about where I think you will like it you may see no more puking.

 

[mgedit]

Thanks Geo ... hope that solves the problem and it was just a case of finding its own level. Think I may have an extra overflow bottle. Cheers, Mike

 

[M_Pied_Lourd]

Here is how the PO had installed mine....



Cheers
Tush

 

[TexasKnucklehead]

Funny how much water expands when it gets warm. This picture shows my overflow bottle, which is hard to reach, but easy to see looking thru the grill. It has a "hot" and "cold" line so I can tell if I am leaking. I also had the radiator neck replaced for a normal depth cap. It draws, and pushes coolant into the bottle. This picture shows a funnel that I used to fill the radiator to the top -just to the bottom of the funnel. I was expecting the level to drop once the thermostat opened, or some coolant to leak around the edges of the funnel. As you can see, the level in the funnel rose, and it didn't leak down until it cooled. If I wanted it to seal, I couldn't be that lucky. So, that's roughly how much air needs to be in your system to keep from puking.