Hello everyone! I'm finishing up after replacing the head gasket and have a few loose connections I'm hoping to get some help with.

I was driving home late at night from a long day of wheeling. Brake & charge lights both come on, and I know from experience that this points to the alternator. I figured it's late, I'm 20 mins from home, and I have a big ass battery. So I decided to keep driving, thinking the battery would get me there or at least close. Take note - this was a moment of stupidity. By the time I noticed signs of overheating and pulled over, it was too late. I opened the hood and realized the alternator belt had broke. You know... The one that runs the water pump...

TRUCK INFO:
'85 Pickup SR5
22re & W56
PS, deleted A/C

Thanks for reading!



Green temp sensor plug in middle of motor, intake side. I believe this is for the gauge in the instrument cluster, correct? My gauge often shows nothing but occasionally shows normal temp for a few minutes. I can't find the mating plug. Does anyone know where this wire splits from the harness?



White two-pin and blue single wire plugs stemming from the back of the intake manifold.



This single wire connector, dropping down near the starter. Sorry for the confusing camera angle. I think this was loose before any headgasket issue, however I'm not certain that the alternator belt could have ripped it free.

A friend of mine thinks it might go to the green temp sensor.



This l'il baby wire string from the harness inside the intake manifold. I'm assuming this is a ground? It looks like it's supposed to connect to an other wire judging from the end. This was for sure loose before headgasket issues.

 

Picture # Plug goes to: (I believe) I have an 87 pickup, and I USED to have an 87 4Runner. For many years, and a lot of work done. I'm a Radar Tech by trade, so I'm very familiar with wires, and figuring out where they go. The same thing happened to mine. A "friend" was borrowing my truck, and the belt broke. He drove it till it overheated, let it cool down for a while, drove it till it overheated, etc, until he got it back to my house. I did have a belt, and tools, in the back of the truck, he just couldn't be bothered to get out in the 110 degree heat we have in Yuma, Az, where I used to live, and fix it. I had to replace the head, and head gasket. Needless to say, he never borrowed any of my vehicles again. ESPECIALLY the 4Runner

A huge help is the silicone dielectric grease. A dab in the female side of any connection can solve a lot of troubles. Just a note.

Here we go!

Picture #

1: I believe it does go to the gauge cluster. Often their bolts, that act as their electrical connection, as well as holding the gauge down, or the very small wires on the gauge itself, come loose, and cause the intermittent operation. I'd check there first. You can also check that the wire into the plug is tight and the pin inside is clean and tight. Sometimes the wire can flex, and break the strands loose from the pin. That doesn't usually make for intermittent operation, it usually causes a failure, but it's worth checking.

2: I might be wrong, but I think the single is the electrical connection for the fuel pressure controller, and the double is for the VSV that controls it. I may well be wrong on those, though.

3: That single with no wire to it may either be not used, or the connection for the 4WD indicator light. IS your truck 4WD? If so, do you have a wire with a green connector on it coming out of the tranny on the driver's side? Does it reach to that plug?

4: Either the ground down to the AC compressor mount, or, if that mount isn't present, where the mount attaches to the engine block. Does that wire go to one of those places? If it does, it may connect directly to the battery Negative Terminal. If so, a ring terminal onto the wire will be the way to go. That way, you can connect it right to the battery negative terminal. With a 1-2" length of meltwall heat shrink, which will provide both strength, as well as protection from the ick in and engine compartment.

Alternatively, if the engine doesn't crank when the key is turned to STArt any more, it may go to the starter, pin B. Trace where the other end of the wire goes. That will be a huge help. If so, a female spade terminal is the correct connector. WITH insulation of some kind, preferably heat shrink with the meltwall in it. Great stuff. Keeps the crud and corruption in and engine compartment out of the connections.

Does any of that help at all?
Pat☺

 

Thanks! Yes, this was definitely helpful!

Okay, so the wire in the 4th pic goes to the thermoswitch in the 1st pic. I separated the two halves of the green round plug and upon looking inside it became obvious only the conne tor from the 4th pic could fit in there, plus I rerouted that branch of the harness the way it's supposed to go and that puts the split within 2" of the plug.

The white and blue plugs I'm fairly certain are for A/C, which I believe the truck had but was deleted.

There are also a couple other plugs I didn't show, but I traced those back to a vacuum solenoid valve that was also deleted. There have been some modifications previous to me owning the truck and they aren't always easy to figure out! 😅

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I have everything back together correctly now, I think. Coolant & oil are filled and battery is connected. I went for a test start and it turns over but won't start; sounds like a lack of compression. I'm worried the head could be cracked internally.

Could this be a timing issue? I didn't adjust valve lash (did this a few months ago when I had the valve cover powdercoated, along with re-torqing the head bolts). Marked the upper sprocket and chain, as well as the distributor shaft and even the location of the distributor tilt. This was all done at #1TDC. I ziptied the timing chain to the upper sprocket and kept tension on it. Then cut a 1/2" block of wood into a trapezoid, screwed some tie wire to the top, and shoved it down between the chain guides to keep it from dropping off the crank sprocket. I feel like I was pretty careful to put everything back exactly as it was. Everything was torqued to the specs listed in my FSM.

Really bummed it didn't start right away. Suggestions to point me in the right direction?


Block of wood & ziptie to keep timing chain locked to both sprockets.

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Is all the intake tubing tightly piped up to to the air cleaner/VAFM???

 

Yes. All I removed was the upper arm going from the VAFM to the throttlebody. It's back on and clamps are tight.

 

Okay...

I confirmed spark by removing the #1 spark plug and laying it on the block for ground. Set my phone camera to record and cranked the motor for a couple seconds. Video confirms spark.

I jumped FP & B+ on the diagnostic port to confirm the fuel pump is working and let it run for a few seconds. Then I wrapped a rag around the cold start injector and cracked the banjo bolt. High pressure. This rules out fuel being the culprit I believe.

 

Will the engine run briefly when starting fluid is applied at the air box intake??

 

No sputter, pops, or farts when starting with carb cleaner, however...

I found the problem! I removed the valve cover to double check the timing and realized NONE of the lifters had any space! They were ALL tight, meaning the valves wouldn't fully close thereby losing all compression. Adjusted the valves to cold specs and it fired right up!

Thanks for the replies!