Thread: 400 getting hot,

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Ok, i have a 400 in my Jeep and it gets pretty dang hot during the summer. Usually creeps up to 210-220. Specs are it's a non bored block, not sure on cam specs, I have the HEI dist. the guy who built the motor used performance parts....so it's not a stock motor. I've had it in my Jeep for bout 3 years now, seems to get hotter each summer with this summer being crazy. Now, a few weeks ago i redid the gasket on the intake manifold, if i didn't get the dist. back in right and have the timing too advanced would that cause the motor to get hotter. The timing is advanced probably around 32 total, maybe a tad more....not more than 39 though. I don't run a shroud (yet) using a 160 deg, thermo.....how can i tell if the thermo. is bad and not opening? I was thinking of mounting an electric fan in front of the raditor and getting a shroud, whould that keep it cool? What about an oil cooler? The motor right now runs very strong....I can chrip my 39.5" super swampers in third, but in 4th gear it seems kinda doggish would that be timing or something else. Just withen the last 2 months i have put a new cap and rotor on, new plugs, new wires, drained raditor and engine refilled with new coolant, new oil......using 10w40 synetic(spelling) Basically I'm curious if my timing is not correct and causing heating problems.....or tops to keep it much cooler.

thanks for the tip, how would i check the flow?

Infrared temp gun works great. You can see the cold tubes that way.

Usually the bottom ones .

Flush the rad, and put a shroud on the fan. Retarded timing is more liable to cause heating than too much advance, as will lean jetting. Jeeps have tight engine compartments, can the hot air get out? Do you have a four core rad? You should.

I cut alot of the fender out to let the air flow out.....i've seen alot of Jeeps with v-8s luve(spelling) the hood, you know the vents. I'm pretty sure i have just a 3 core rad. never thought of that option.....know where i can pick up a 4 core, for a decent price. Also, i have a winch sitting in front, I know that reduces air flow.

http://www.radiatorexpress.com/defau...f_source=CINDY

Do you have 350 heads? Maybe the builder didn' t do the steam vent holes right. I've seen them drilled wrong and cause heating problems. Also, try running it without the hood for a while, if airflow is the problem, this will make a difference.

One more thought--does it just heat at low speed? the hot air could be recirculating under the bumper and back through the rad. A splash pan/skid plate will sometimes stop that. A Jeep should have one anyway!

the heating issues occur at higher speeds, more rpms. Where when i'm cruising at low speeds it cools some or at least stays level. i just might take the hood off and see what i get and go from there.

Heat increasing steadily at higher speeds usually means not enough radiator . Find the biggest 4-core that will fit.

just checked the head numbers and i got 3973487, which according to the lists i've checked say there 71-72 LT1 heads from a 350......so maybe the builder didn't drill the steam holes correct. Is there a way to check without pulling the heads or.....should that be a last option?? I have good compression in each cylinder so the head gaskets must be fine, which i would think if the heads were not drilled the steam or pressure would have cracked a gasket by now.

Some good suggestions thus far. I would opt for a shroud ASAP.

My 53 Willys Station Wagon has a 360, To cure its hot problem I Louvered the hood ,This Helped the most. Took out the uncoated headers and got coated ones, This was the second biggest improvement. One of the first things I tried was to put a second elec fan in front of the radiator , it made thing a little worst, it blocked more air flow a speed I also have a 2core alum radiator ,mechanical fan ( Tried Electric didn't work)