lpg converter running cold

[chief01]

converter froze up while cruising on the freeway , managed to start on petrol seems to run ok now but heater running cold , flushed out heater hoses, converter and matrix,purged cooling system , seems hose to converter runs hot but converter to heater is only warm maybe water flow is compromised. car is a 98 discovery v8 any advice appreciated

[Titch101]

I had a similar problem in my old panelvan it turned out i had a hole in the radiator and the lack of water caused the converter to freeze over so i would check the amount of fluid in the radiator and/or any leaks in the coolant system.

[bee utey]

If the converter is in line with the heater then any blockage in the heater circuit will cause reduced flow and freezing. If it is tee'd into the heater lines then you may have a failed thermostat. Without the thermostat closing when cold you won't have enough pressure to flow the converter. An internal gas leak in the converter may cause some problems but usually causes freeezing quite early during a run.

These days I tend to run converters off the bypass line from the manifold (thermostat area) to the top of the radiator. If you upgrade the outlet to 10mm and run new hoses without the throttle body heater that seems to give good results. I include a pic from a RRC I am currently converting.

[350RRC]

Low water or an airlock. Search for airlock remedies, easiest is parking on a decent angle so the bung in the top of the rad is the highest point in the system.

Remove coolant res cap & bung (when cold so you don't get scalded), start her up and top up the rad via bung hole. You'll see when the thermostat has opened with the coolant starting to circulate, get all the air out by topping up and replace the bung when overflowing with coolant.

Top up reserve to warm level and replace cap and all should be good.

cheers, DL

[DEFENDERZOOK]

if its running through the heater plumbing....then it will rely on the heater being on.....

make sure the heater tap is working and allowing the coolant to flow through it....

[ozscott]

I got sick of oiling converters so I installed an online brass device - thermostat - in the heater hose near th converter that ensures the water into the water is the correct heat. The theory is that too hot and the LPG cracks again inside the converter leaving residue and wrecking diapraghms and valves. There is a site in the us about it and more cabs in qld are using them. So far so good but my heater runs much cooler because of the slower flow through the matrix. I thinking of running a bypass because of that. Cheers

[alien]

converter froze up while cruising on the freeway , managed to start on petrol seems to run ok now but heater running cold , flushed out heater hoses, converter and matrix,purged cooling system , seems hose to converter runs hot but converter to heater is only warm maybe water flow is compromised. car is a 98 discovery v8 any advice appreciated
My first thought given the loss of heat in the heater also was that your thermostat was stuck open alowing for cooler runing tempratures.
What was the engine running temprature? Same/colder/hoter.

As you said the temprature differance on the hose either side of the converter is possibly effected by low coolant temprarure also.
The water is heating up the converter to change the Liquid to a Gas.

Let us know what you find.

[101RRS]

My LPG was rigged to run through the heater - before I realised this I could not work out why LPG played up all the time - had the heater off.

Having the heater on to run LPG is not a good arrangement so I put in a T junction on either side of the heater so it could be bypassed - in this pipe a put in a tap. With this tap half open there is enough heated coolant going to both the heater and LPG. In reality I have this tap closed in winter with asll coolant going through the heater and in summer the heater is isolated.

Works well.

Garry