I hope you guys can help me...

I got a 93 SC300 and I swap in a 1jzgte in it. Everything went in fine and the car start up.

Here is where the problem I have. There is no coolant flow to the heater and back to the radiator. Would anyone be able to let me know what is wrong or if you have the same issue, how did you solve it?

I also put on a new thermostate. I haven't change the water pump yet. I know I should when the engine was out. but I'm not worry about installing a new one in later. Would the water pump be the problem? I didn't see any dripping from the pump hole. So basically no flow to the heater core and back means the engine is not gettting coolant.

I just like to here from you guys if the pump is the issue in this situation before I start tearing it out. This is a project car for me so. I not really in a hurry. Just like to work out the bugs. lol

Thanks for any help in advance and confirming what I think I might need to do, which is replacing the pump.

 

I thought on the 1jz's you had to switch the water pump out.And i Believe that in japan they use different coolant.Maybe its block up with some thing.Try to search it.I think it was on this forum a guy had a similar problem.Take out the thermostat.And put it back together.And then start the cat and see what happens.

 

How did you determine there is no flow?

 

You need to prime the system or the coolant from the radiator will not go into the engine

 

Wheel2-I might try the no thermo. next. Was thinking of doing that,but want to hear from fellow Lexus owner first.
And I'll do some more searching on that.

Ryan-I pull out both of the small coolant hoses form the back of the engine that run into the heater. No water came out of both end. And check the bottom radiator to see if it get hot and it wasn't. My water temp gauge hit Hot asap. The top radiator hose was hot from the engine but not the radiator itself either. I let it run pretty long. So I decide to shut it down before I bust something.

I'm going to try to narrow it down and put it off my check list on my trouble shoot list. No Thermostate and I'll let you know.

Thanks for the info. Anything will help narrow it down.

 

I have to admit. I'm not good with tech word, but what do you mean by "prime the system?" Is it like a air release valve and if it is I have no idea where that is on a 1jzgte.

 

Did you do the water temp gauge mod? From what I read if you didnt then the gauge will peg hot quickly. Other than that I hope you get a solution to this as I am hopefully going to finish my install on saturday.

 

I've heard that you have to put resistors on the Tach, but didn' hear anything about the temp gauge. It does peg hot quickly, but would that stop it from making the coolant flow? I will also try that. Will put that on my to check list. lol

 

You said that there is no flow back to the radiator.And so if you take the thermostat out it will flow.Leave the radiator cap off and you will see the water flow.No flow then Maybe water pump.Or something is stuck in the system.Plus if there in no flow to the radiator then there will be no flow to the heater.Because the water/coolant is not flowing.

 

Thanks wheels, that make sense. I will take the Thermostate out. See if there is flow. Maybe even clean out the System and flush it and start over. After that I will have to get my hands dirty again and change the waterpump.

 

Ya your welcome.When ever I get my swap I am going to replace every thing.As in front assembly.New water pump/oil pump/alternator and so on.Just to be safe so I dont have any problems.

 

Oh and let us now how it works out.GL

 

UPDATE:

Took out the Thermostate and the water flow fine. Found out that the Vacuum line for my VSV was connected at the wrong spot. The car seem to run smoother with a good coolant flow. Waterpump works fine, so I won't have to do a change over yet. But I'm still having issue with the temp gauge. It spike up to high right away. Wondering if the sensor is bad or is it just the gauge?

Once I feel comfortable with the gauge not spiking high right away. I'm putting back the thermostate and see again. but for now anyone would know about the temp gauge issue? or a link of some with this issue.