Hello members,would like some assistance on an overheating issue, after running the machine for about two hours, the temperature gauge will rise to near the red zone, coolant will spill through the cap breather and its a constant flow having to top up almost 20 litres of coolant the next day, after overheating if i idle the engine the gauge will only drop abit and quickly get back up, so far we've changed the head gasket, pump inspected and seems ok,today on closure we did a thorough radiator clean up and i will observe tomorrow, what would be the issue, attached is the serial number and breather spilling, Thank you all.
Hopefully you just need to clean the radiator. That's the first step in any case. The bottom picture shows the fan guard plugged with oil, dirt and debris, so it's safe to assume the radiator is much worse. Here, I would blow it off with compressed air and a small blowgun, then rinse with water, then soak with a degreaser called "Purplepower", dishwashing liquid works good also, even diesel fuel if you keep it off plastic and rubber but don't soak with water first if you use diesel. Rinse until clean, repeat with compressed air. Don't use a water pressure washer unless you're extremely careful. Often it will be easier to remove the radiator to get it completely clean. Use a light on the other side to check if it's clean, every fin, every tube.
Actually the dirt on the radiator grill is dust mixed up with the leaking coolant,am doing bush clearing so there's alot of fine dust and debris but we cleaned it all up, i will observe and hopefully its the only issue, thanks.
Use a IR temp gun and record the radiator inlet hose temp vs the outlet hose temp
With the type of work you are doing and the levels of dust generated the radiator will probably require cleaning every day. Please post a better photo of the radiator core, because I agree with Delmer that the small area of radiator and guard visible in your photo above indicates that the radiator is nowhere near as clean as it needs to be, especially in view of the type of work you are doing. If you have not changed it yet I would also suggest a new OEM radiator cap, because I imagine there would be a lot of poor quality Chinese parts in the market in your location. As Mike says, taking the temperature of the radiator inlet and outlet will give you a very good indication of the radiator efficiency. Based on the photo above I am not hopeful of the results you will get.
OEM radiator cap Part Number is 294-3342. It is an 11.5psi cap. Judging by the "7#" marked on the cap in your photo it could possibly be 7psi and maybe not original.
That is a common cap I see around here, 7# definitely means 7 psi.
That was my worry, the cap pressure appears to be too low. Would someone like to comment on these specifications.? I initially thought it was 11.5psi but on a 2nd look it could be that the OEM radiator cap might be rated as high as 16.5psi. "Pressure at cap seal with 30 CC air flow is 80.0 kPa (11.5 psi). Pressure to cap open with 700 CC air flow is 113.7 kPa (16.5 psi)."
I think that means if it is being lifted off its seat with 30cc of air or flow (per second? who knows) it will be 11.5 psi in the top tank, if it is really whooshing past at 700 cc (again per unit of time) then it will get as high as 16.5 psi. However, I don't really think that going from a 7 psi cap to an 11.5 psi cap is going to make that much difference in terms of overheat/overflow. But is the 7 psi cap even right for the filler neck, seating and building pressure? Is it any good in the first place?
Will the 7psi cap even hold 7? In the racing days we swapped a motor from alcohol to gas. Dang thing would overheat after 2 laps. Chased our tails on it for an embarrassingly long time. Finally realized we were using like a 10# cap due to alcohol running so much cooler. Went to a 16 or 18, may have even been 20# and boom. Cool as a cucumber. Before I did anything else I’d get the correct cap and make sure it seals properly. Make sure the neck itself isn’t out of whack too.
That's what I was kinda thinking.
Seems the radiator cap was the issue, i put back the original one it seems the one they had bought wasn't genuine, no loss of coolant and temperature is rising to the normal ranges and nothing beyond,thank you all for your input
We’ll call me surprised - not…..
I would suggest that you order a brand-new OEM cap, just in case. I posted the Part Number further up. The one you have installed right now has definitely seen better days.