I have an 88 Lb9 motor. What is the deal with the sender in each cyl. head? I figured the one on the passenger side is definately my temp sender as it is run straight into the water jacket. My gauge was also not working at all and it had a burnt up plug. Now what is the one on the driver side for? It looks just like the sender (in the same location too) for temp. on my 86 C-10 chevy truck! Should one of these holes just have a pipe plug in it or something? God only knows what the idiot who owned this car before me has done, he is the reason I am repowering now even! Thanks!!

[This message has been edited by MikeC.86Roc (edited September 17, 2000).]

 

Driver's side sensor is for gauge & I believe ECM input; passenger's side to control secondary fan turn on point.
Regards, FJK

[This message has been edited by FJK (edited September 17, 2000).]

 

On all chevy small blocks, the sender should be located beteween #1 and #3 plug on driver's side, although some people put it on rt or in intake manifold. in side of engine gives you better 'average over time' temp.

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1966 c10 panel
1968 c20 350, 350
1982 camaro 305, th200

 

Close -

The left (drivers') side sensor is used to signal the dash guage, the right sensor is no more than a temperature switch used to operate the secondary cooling fan, and the center sensor (on the front of the coolant crossover in the intake) is used to signal the ECM.

BTW - The other sensor on the right side near the starter is the knock sensor. It is actually in the cylinder case, not the head. There are also two oil pressure sensors, one near the distributor and one near the oil filter adapter cast on the case. Fortunately, there is only one oxygen sensor, instead to the four that appear on some newer engines (soon to be six).

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Later,
Vader
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"Make Me Bad"
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[This message has been edited by Vader (edited September 17, 2000).]

 

I should know better & leave the finer points to Vader.
FJK

 

Not all 3rd gens have the oil pressure measured by the distributor. 1991 RS 305 is by the oil filter only.
Later

 

FJK,

Not at all. You'll catch me missing the boat from time to time like almost everyone else, and I'm glad there are other members like you to keep me honest. I hope to learn something every time I make a mistake (except in spelling and punctuation - I never seem to catch those). Good example - Matt clarified even further.

The main thing is that the questions get reasonably good answers. After making a glaring error several months ago, and subsequently being corrected by Mr. GhoSSt (an LT1/LT4 authority, among other skills), I've been very careful to try to give good, complete information, or at least give suggestions that won't cost anyone money, time, or physical harm. We're all here to learn, and I'm sure you could teach us all a thing ot two...I've seen your replies.

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Later,
Vader
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"Make Me Bad"
Adobe Acrobat Reader 4.0

 

Ok, this is a great through explaination that I needed. As a matter of fact, I went to my local dealer today and purchased many of the senders for my new motor I am building. I am converting from lb9 to a zz4 partial, and I wanted to buy all new senders just as piece of mind (including the 350 knock). Funny thing is, the parts guy and I found most of them just fine.. Except the fan sender in the pass. side cyl. head. I have a printout of the parts diagram for an 88 350 and god knows where the fan sender is. I told him it was a weatherpack type connector with a male terminal in the harness and he just kind of looked at me like he was clueless.. Got a part # Vader?
As for the sender in the driver side cyl head, you guys were right on! My gauge was not working and the white connector in the same harness with the ox. sensor and oil??? sender was completely just hanging loose.
Now for the last question(s)..
What is the sender above the oil filter for? I thought the Bell looking sender near the dist. was the pressure sender.. Does the other one have something to do with fuel pump cutoff in an emergency event?
And last, I priced the cold start sender (switch?? what is this??) at the front of the intake too.. It was like 45 bucks! Should I just leave it alone and re-use it on my new buildup?
Again thanks alot, I'd be lost without all of your help!

 

Mike,

On my '86 TA, the oil pressure sensor beneath the distributor at the rear ledge of the block is used for the fuel pump auxilliary power, and the one near the filter adapter (the bigg'un) is used for the oil pressure guage on the dash. I'bve heard others say that theirs are just the opposite, and it really doesn't matter where they mount. The larger of the two is generally used for the guage/light, however.

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Later,
Vader
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"Make Me Bad"
Adobe Acrobat Reader 4.0