Author Topic: 1987 Silverado V10 from the frozen north  (Read 8911 times)

Offline nbarr7

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Re: 1987 Silverado V10 from the frozen north
« Reply #45 on: March 25, 2022, 08:04:20 PM »
The transmission issue was resolved (not by me) and it's a bit embarassing as it was a simple oversight on my part. I'll try to swallow my pride and post about it in the hopes that if anyone else ever has this, they'll learn from my idiocy. Video coming soon.
1987 Silverado V10 Fleetside

Offline JohnnyPopper

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Re: 1987 Silverado V10 from the frozen north
« Reply #46 on: March 26, 2022, 12:32:54 AM »
Humility takes courage.

Those who are 'never wrong' are weak.

You will be a better man.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline nbarr7

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Re: 1987 Silverado V10 from the frozen north
« Reply #47 on: March 26, 2022, 03:52:25 PM »
Late March video update on the truck. Progress is being made. Despite my inadvertent attempts to thwart it

https://youtu.be/spD-bltGjqY
1987 Silverado V10 Fleetside

Offline Mike81K10

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Re: 1987 Silverado V10 from the frozen north
« Reply #48 on: March 26, 2022, 04:05:51 PM »
I know it must feel good to drive it, I have not driven mine for years and look forward to to first ride.
"Tell me and I forget. Teach me and I remember. Involve me and I learn." -Benjamin Franklin

Offline frotosride

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Re: 1987 Silverado V10 from the frozen north
« Reply #49 on: March 27, 2022, 05:29:33 PM »
I know it must feel good to drive it, I have not driven mine for years and look forward to to first ride.
Amen, can't wait to have that feeling again!
"Beat it like a red-headed ford"
1987 v10 Silverado(LQ4), 87 R10,83 K20, 83 cucv 6.2 Detroit
2006 Boulevard M109R 109 cid,2019 M109R BOSS
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Offline nbarr7

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Re: 1987 Silverado V10 from the frozen north
« Reply #50 on: April 29, 2022, 11:46:53 AM »
New Video update is coming soon with info on timing, replaced ignition parts, and some basic cosmetic work.

In the meantime, I seem to be losing coolant. No smoke at all in the exhaust, so I don't think it's a head gasket. It's in a gravel driveway so leaks are hard to see. Almost seems worse when I drive it, like the transmission is involved or somehow driving it down the road increases the loss. I know I likely need a pressure tester, but wondering if anyone knows any obvious places to look (besides clamps on the upper and lower rad hoses which seem dry - the trans hard lines do seem sort of chewy, but I have to look closer to see if there are any actual holes)

sorry for the delay. Lots of video clips to put into an update soon
1987 Silverado V10 Fleetside

Offline JohnnyPopper

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Re: 1987 Silverado V10 from the frozen north
« Reply #51 on: April 29, 2022, 12:40:19 PM »
I doubt the trans is involved, as much as driving it builds up heat/pressure by itself.

Place a piece of cardboard under her next time you park.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline bd

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Re: 1987 Silverado V10 from the frozen north
« Reply #52 on: April 29, 2022, 04:04:51 PM »
...I likely need a pressure tester...


This ^^^^^   Inspect all of the connections you mentioned as well as the radiator core and tank seams.  If a leak Is not visually evident under pressure, see how long the cooling system maintains 20 PSI - how quickly it bleeds off.  With the cooling system full and the pressure tester fixed in place of the radiator cap, start the engine dead cold to see how quickly cooling system pressure builds from zero to 20 PSI; just don't let it build beyond 20 PSI. 


Is there an intermittent "sweet odor" inside the cab?  Check the engine oil on the dipstick for water droplets or tan colored mayonnaise.  Inspect the weep hole on the water pump neck for coolant tracking.  Closely inspect all of the accessible cylinder block welch plugs, including the one hidden behind the starter and the two in the rear of the block behind the flywheel/flexplate.  Remove and inspect all of the spark plugs to see whether any are exceptionally clean.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline nbarr7

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Re: 1987 Silverado V10 from the frozen north
« Reply #53 on: May 29, 2022, 12:44:13 PM »
I got a pressure tester, but have since encountered a rough idle/timing issue, so I haven't prioritized the coolant situation. It does seem to get to about half full in the radiator, and then seems to stay at that level. I don't have sweet odors in the cab nor water droplets in the oil that I can see.

Here's a video that explains some of the updates, but lest this seem like a plug for some youtube show (which it's not - videos are private and just for information on this forum) I'll summarize here:

I took the bed off, and went down and got the frame patched. Because of the faulty selector valve, the left hand tank (which I never used) started gravity pouring gas back to the selector, and actually started the selector valve on fire from welding sparks. So... after some melty wires and fully deleting the selector valve, I'm now running without a left hand tank at all, and just plugged right into the right hand tank with no selector valve - which is currently on the ground until I can drill out the patch panel on my frame and re-hang my gas tank.

The big problem is that somewhere in early spring I started having a high idle that the truck just wouldn't come down off of. We checked for vacuum leaks, re-gasketed the throttle body, replaced the iac valve, and did some timing work. Now here's where things get weird. We may have been unplugging the wrong wire to put the truck into 'base timing" mode and so we thought all the computers were off (in my defense a professional mechanic was with me at this time). To that end I replaced the icm in the distributor, and then when that didn't take the high idle down, I replaced the ecm with a brand new one. Now, I have to admit to stupidity/ignorance (since I was replacing it alone and have never worked on cars before). I unhooked the battery when I put in the new ecm but I didn't know I needed to swap the modules from the old ecm at first. I know I hooked up the battery with modules out - I may have tried to start it that - way it's been so long I can't recall. I finally found online the info that I had to swap the chips/modules, and started the truck and THAT was the moment that it started to run really really rough. Like way out of time and backfiring and everything.Now it seems to not stay at the same timing. And still starts hard and runs weird. I had it timed at almost at zero yesterday, and adjusted the distributor just a little, and then I couldn't even find the timing mark on the harmonic balancer 2 minutes later. Like it's either shifting timing on its own, or... I don't know.

After all that, I also swapped out the spark control computer and map sensor just in case. No change.

Thinking maybe I had fried the ecm by putting power to it without those chips, I went and got a cheap used ecm out of an 88 tbi burb, and it does the same thing. So then I put the old icm back in the distributor, wondering if I had fried that. Same thing. So... Did I smoke a sensor somewhere that's giving the ecm a bad reading? Or would the timing chain just happen to stretch at the exact time I put a new ecm in? I'm really stuck here, and can't really do anything else diagnostic on the truck when it wont' run right. Yes this is likely all my fault, but I know it takes money (and/or time) to "go to school" and I"m ok with that, generally. The point is to learn. I'm just... I'm needing some actual progress here. I feel like after all the work I've done, the truck has just gone backward. The only thing I seem to have done semi-right is the fuel system - which in my defense is what I bought this truck under the assumption that was all it needed. All this (and more) is explained in the May update video linked below:


https://youtu.be/Z8duMLKPOzk




1987 Silverado V10 Fleetside

Offline RossVE

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Re: 1987 Silverado V10 from the frozen north
« Reply #54 on: May 29, 2022, 02:41:30 PM »
I most likely can't help much, I know next to nothing about injection systems and sensors. But I would start with the assumption that something in your parts changes may be at fault. I know what I'm saying is pretty basic, but I would start with checking every possible wire for breaks and bad spots. Every connection for loose wires or corrosion, etc. I once walked 3 miles in midsummer heat because my Chevelle had run out of gas - only to find out that the ignition wire on the back of the hei distributor had come loose.
  Is it possible that over the winter a mouse has decided to use your harness to snack on?
  Good luck!

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Offline bd

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Re: 1987 Silverado V10 from the frozen north
« Reply #55 on: May 29, 2022, 03:21:24 PM »
STOP throwing parts at it!  You'll just burrow into a deeper hole than you're in, already.

The high idle issue probably was the cruise control link that you eventually disconnected.  It is a common problem.

Begin by validating the ECM I and ECM B fuses in the fuse box - physically remove and inspect them.  Disconnecting battery power from the ECM will clear any stored codes, many of which may be false reads.  Next, replace the fuel filter and measure the fuel pressure using a proper test gauge.  TBI systems are exceptionally sensitive to fuel pressure. 

Fill the cooling system and start the engine.  Keep it running for up to a minute and then check the ECM for stored codes and write them down.  Use a scanner if you have one, otherwise retrieve the codes manually.  Post all of the results.

You really need to determine where the engine coolant is going.



FYI - The ESC timing bypass (for base timing adjustment) is the tan wire with black tracer passing through the single wire Weatherpack connector; see image.

For normal vehicle operation, the ESC bypass should be connected (plugged together).  Base timing should be checked and adjusted only with the engine at normal operating temperature and the ESC bypass disconnected.  Checking engine timing with the bypass wire connected is a waste of time since timing is controlled by the ECM and could be anywhere, thus appearing erratic. 

If you are compelled to validate the timing chain, refer to How to Evaluate an Engine Timing Chain in the Technical Forum.

Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline nbarr7

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Re: 1987 Silverado V10 from the frozen north
« Reply #56 on: May 29, 2022, 03:59:19 PM »
My apologies. I'm actually changing some of the new parts back just to eliminate so many variables. Fuses are good - I checked all my fuses yesterday. I will have to buy or rent a fuel pressure gauge. I don't have a scanner, and currently my dash is all wonky since I took my taillights off with the bed (i.e. my check engine light isn't even on at all so I don't think I can manually read codes) I'll also see if someone has an old scanner. Again, sorry for going about this the wrong way - I know throwing parts at things isn't the answer, but many of those parts were recommended by a mechanic, but I think regardless of what he says, I need to sort of start over.
1987 Silverado V10 Fleetside

Offline Mike81K10

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Re: 1987 Silverado V10 from the frozen north
« Reply #57 on: May 29, 2022, 04:09:41 PM »
Scanner can be found at reasonable prices. Having tail lights disconnected/removed should not cause any problems. My electrical system is working OK right now without the bed harness connected to any of my tail lights (my bed is removed right now).
"Tell me and I forget. Teach me and I remember. Involve me and I learn." -Benjamin Franklin

Offline bd

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Re: 1987 Silverado V10 from the frozen north
« Reply #58 on: May 30, 2022, 10:40:56 AM »
...my check engine light isn't even on at all so I don't think I can manually read codes...


NO "SERVICE ENGINE SOON" LIGHT -CHART A-1 - (TBI)

Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline nbarr7

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Re: 1987 Silverado V10 from the frozen north
« Reply #59 on: May 30, 2022, 04:45:52 PM »
I discovered that if I hold the light bulb in place with my finger (forcing better contact with my somewhat floppy copper strips) I do indeed have a check engine light that goes off once the vehicle is running. Jumpering the obd port now

*edited because I remembered I caused a code
« Last Edit: May 30, 2022, 06:57:56 PM by nbarr7 »
1987 Silverado V10 Fleetside