110v8 Posted April 22, 2009 Share Posted April 22, 2009 does anyone know which thermostat temp i need, i have a 4l 42d engine with edelbrock manifold fitted in a defender. i have at the moment a 88 thermostat fitted and the fans are on a lot, any hill or traffic lights and on they come, i do a lot of towing and they are constantly on, i am considering fitting a 82 thermostat as on original 3.5 15g engine. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted April 22, 2009 Share Posted April 22, 2009 To run engine lowest temps run a 74 degree unit from an early 2 dr carbed engine around 1970s Nige Quote Link to comment Share on other sites More sharing options...
110v8 Posted April 22, 2009 Author Share Posted April 22, 2009 would 74 not be too low, i also run lpg Quote Link to comment Share on other sites More sharing options...
Aragorn Posted April 22, 2009 Share Posted April 22, 2009 most modern petrols use a 90c thermostat and a 100c rad fan switch. If you currently have a 88c thermostat and an 88c rad switch its no wonder the fans running all the time... You really want the engine running around 90c for optimal efficiency, as long as the fans are keeping the temp inline i wouldnt worry about it too much, however its worth noting that often a radiator is MORE efficient when moving with the fan off. Ie doing 50mph with the fan running usually causes that much turbulence that you actually end up with less airflow than without the fan running. I would leave your engine stat alone, fit a decent aftermarket water temp guage so you can get an idea of the actual temperature of the water, and perhaps install a 95 or 100c rad fan switch, so the fans are only kicking in when needed. It should be noted that the fans really only should run when stationary or in slow moving traffic. If they're coming on while towing then i suspect your radiator is struggling to keep the temps down, and in that case changing the stat is only going to act as a band-aid to the real problem... You need to flush or change the radiator. Quote Link to comment Share on other sites More sharing options...
Quagmire Posted April 23, 2009 Share Posted April 23, 2009 I run an 82 deg stat with the Kenlowe set to come on at around 88-90 degrees. As Aragorn says you should find that the fans only really kick in when you come to a stop. I drive 33 miles to work and the fan usually only comes in for the first time when i drop off the M4 and come to traffic lights, as thats when you get heatsoak. Even then, i can sit idling for 2-3 minutes before this happens sometimes. With this setup my gauge never wanders from the 12'Oclock position- LPG is quite happy to run at this temp too. Quote Link to comment Share on other sites More sharing options...
110v8 Posted April 26, 2009 Author Share Posted April 26, 2009 i have tried raising the fan temp as suggested but had the overflow tank let loose with the pressure, the fan switch is from rs components and is the type with cappilliary pipe into top hose and adjustable dial, i set this to 90 and watched the temp gauge (sender and gauge for 3.5 lr engine,this a 4l) go up to 3/4 gauge when fans cut in and i saw overflow draining,normal running without much load or speed the gauge reads just below 1/2 and fans cut in just above 1/2 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.