Alright, I have been posting in my introduction thread, this is a question that I do believe should be posted in a new topic due to its perplexing nature.

I just got the 1.3 back in the Sami.  I had it rebuilt at the local machine shop that I seem to spend more time at than anything.  I have had COUNTLESS engines rebuilt/worked over at this shop, very reputible.  I used the Lowrangoffroad master kit with HC pistons, .20 over, new EVERYTHING, water pump, oil pump, fan (flexlite electric), radiator (aluminum eco from LR), alternator (GM).

The issue its having is that it gets hot, its damn close to the H.  This is really worrying me.  The fan is on a switch, I have tried these combinations to no avail:

-Fan on from startup
-Fan on at 1/4 temp
-Fan on at 1/2 temp
-no fan at all

If its on from startup and I shut it off when I hit about 30mph, it will hold temp, unless I am pushing it to over 3,200 rpm's, then it will proceed to get warmer, and once it starts getting warmer, no decel or fan of or on will make a lick of difference.  I am seriously at a loss on this one.  Any suggestions would be greatly appreciated!!!!

Oh yeah, It also has an Isky cam.

First - get a temperature gauge with numbers or an ir gun - damn close to the H isn't exactly informative.

Second - there are just too many variables to pinpoint anything from a distance - you're going to have to check things off one by one - the problem can be one of excessive heat generation, lack of coolant circulation, or insufficient heat removal.

Excessive heat generation - possible lean mixture or advanced timing - it is possible that the macine shop screwed up and the bores are a hair too small, but that's not the sort of mistake a competent shop makes too often - I don't see the LROR stuff being the cause, one reason being that I'm using the LROR +0.20 HC pistons myself, but everything else in build was OEM Suzuki.

Lack of coolant circulation - defective thermostat, bad water pump, blocked radiator - you say a new radiator & pump (make sure the impeller doesn't spin on the shaft) but don't mention the thermostat - kinked or collapsed hoses.

Insufficient heat removal - fan too small (inadequate diameter, insufficient CFM), possibly wired backwards - it needs to pull air if it's between the engine & the radiator, push air if it's mounted in front of the radiator, no shroud, radiator too small.

I think I've covered it there...

Everything is new. Even the t-stat, fan is correct, water pump is functional. I had an old hot rod guy look at it tonight and mention the fan spacing is completely incorrect, the supplied shroud/rubber surround does not put the fan far enough from the radiator. He suggested going back to the original engine driven fan. I'm thinking that's pretty plausible. Also, heater blows hot, All hoses are get hot/warm to the touch. One thing I did notice though, when you blow smoke through the radiator, the fan barely pulls it, also, direction is correct. Pulled t-stat when I got home, dropped in a pot of water with a temp gauge, opens at 182, 2 degrees over, not enough to cause concern.

Another thing, if I'm building a truck, I get pretty anal, if a part seems to be even moderately worn, it gets replaced.

Everything is new. Even the t-stat, fan is correct, water pump is functional. I had an old hot rod guy look at it tonight and mention the fan spacing is completely incorrect, the supplied shroud/rubber surround does not put the fan far enough from the radiator. He suggested going back to the original engine driven fan. I'm thinking that's pretty plausible. Also, heater blows hot, All hoses are get hot/warm to the touch. One thing I did notice though, when you blow smoke through the radiator, the fan barely pulls it, also, direction is correct. Pulled t-stat when I got home, dropped in a pot of water with a temp gauge, opens at 182, 2 degrees over, not enough to cause concern.

With the fan running there should be significant airflow through the radiator - that can well be the cause of your overheat - refitting the original fan & shroud, even if only temporarily, might help you pin down the problem area.

Something that I'm not comfortable with is that you say the temperatures continue to climb, if the revs are over 3200 rpm - on a flat open road (meaning no hills or low gear operation), you should be able to exceed that indefinitely with no fan, and just the forward motion of the vehicle to force air through the radiator.

Two possible causes are some sort of air flow restriction - OR - the engine is generating more heat than normal - I had mentioned advanced timing as a possible cause, and yes, I was thinking of ignition timing, which you say is at 10*, it might be worth the time to recheck the cam timing, if that's retarded the engine can also generate tremendous heat.

How exactly do you check the cam timing? I need to buy a new clutch before I put factory back on, it doesn't have any resistance when spun.

Cam timing is a matter of lining up the marks on the pulleys - you'll have to remove the timing belt cover, and you'll see a marks on the crank & cam timing pulleys, the crank pulley mark lines up with a pointer on the oil pump and the cam pulley mark lines up with a notch on the back plate.

Make sure you're turning the engine in the correct direction when lining up on the crank pulley marks, and if the cam pulley appears to be 180* out with the crank pulley lined up, just turn the crank one more revolution - I'll try to find you a picture.

Edit..



If you change the cam timing you'll need to reset the ignition timing afterwards.

Ill take a look at that today.  On another note, I pulled the coolant temp sensors female connector and re-crimped it do it fits tighter, it didn't get as hot anymore... hmm.  I noticed to that it doesn't have a engine to body/frame ground strap.  Just battery to block and battery to firewall...  what issues could this cause?

mmmm - that's kind of why I was suggesting a gauge with numbers, or an IR gun - to find out if there is an actual overheat condition.

Lack of a proper ground does affect the gauge readings, although I can't remember whether thry read higher or lower - having a missing block to battery ground is usually a bigger problem, but, adding a block to boy/frame ground isn't difficult you could try it, see what difference (if any) it will make.

Okay, took today off to figure this out, at least then I have a 4 day, gotta love flex weekends.  Im going to have the mrs get a ground strap while she is out, another thing, right below the coolant temp sensor, there is another sensor that is much larger with a 2 prong white barrel connecter that runs into the harnes.  What is that one for? reason I ask, i have a tripple gauge set here that came with the truck, its mechanical for the coolant temp.  Is there any other ports for coolant I could possibly use?

Okay.  I bought a new electrical coolant temp guage, it came with its own sending unit, rethreaded the sending unit so its same as sammy.  Fire it up, runs to 200*, tstat kicks open, drops to 185.  Get it out and drive around, it goes to 220 and holds steady.  I don't get it, im at a loss now.

You stated " everything is new. "   Does that include the radiator? Sounds like your not getting enough flow through the rad, by both the fan and coolant circulation.

here you go, the only thing not replaced was the carb, headers and intake manifold.  from oil pan to intake everything else was replaced, from radiator to heater core, everything replaced.  Im going to warranty the tstat her in a sec, soon as coffee is good.  After that i thing I am going to run an a/w mix of 30/70, and possibly redline watter wetter.