Coolant leak 1991 Silverado, 350 v8, looks like intake manifold gasket
May 13th, 2019, 10:16 PM
#1
CF Beginner
Thread Starter
Coolant leak 1991 Silverado, 350 v8, looks like intake manifold gasket
I have a pretty nice (still) 1991 Silverado with 350 V8, 5 spd, 4WD. 189K miles. I've had it 11 years, never any engine trouble. Yesterday, started OK, lacked power, (feels like it was running on about 4-5 cylinders), had check engine light. Lifted hood, coolant leak obvious, I first thought was thermostat housing, after closer look it seems it might be the intake manifold gasket, front of engine, driver side.
Questions:
1. I have an OBD II scanner. Does this truck have scan capability to find why check engine code?
2. If it's a manifold gasket, how bad a job is this? Truck has A/C, power steering, throttle body injection
3. No obvious coolant in oil, have yet to check for oil in coolant.
4. How much damage did I possibly do running it 3 miles before I actually lifted hood and looked at engine? (yes, that was dumb, but I only had a short run it had to make)
Questions:
1. I have an OBD II scanner. Does this truck have scan capability to find why check engine code?
2. If it's a manifold gasket, how bad a job is this? Truck has A/C, power steering, throttle body injection
3. No obvious coolant in oil, have yet to check for oil in coolant.
4. How much damage did I possibly do running it 3 miles before I actually lifted hood and looked at engine? (yes, that was dumb, but I only had a short run it had to make)
May 14th, 2019, 12:43 AM
#2
CF Monarch
I have a pretty nice (still) 1991 Silverado with 350 V8, 5 spd, 4WD. 189K miles. I've had it 11 years, never any engine trouble. Yesterday, started OK, lacked power, (feels like it was running on about 4-5 cylinders), had check engine light. Lifted hood, coolant leak obvious, I first thought was thermostat housing, after closer look it seems it might be the intake manifold gasket, front of engine, driver side.
Questions:
1. I have an OBD II scanner. Does this truck have scan capability to find why check engine code?
2. If it's a manifold gasket, how bad a job is this? Truck has A/C, power steering, throttle body injection
3. No obvious coolant in oil, have yet to check for oil in coolant.
4. How much damage did I possibly do running it 3 miles before I actually lifted hood and looked at engine? (yes, that was dumb, but I only had a short run it had to make)
Questions:
1. I have an OBD II scanner. Does this truck have scan capability to find why check engine code?
2. If it's a manifold gasket, how bad a job is this? Truck has A/C, power steering, throttle body injection
3. No obvious coolant in oil, have yet to check for oil in coolant.
4. How much damage did I possibly do running it 3 miles before I actually lifted hood and looked at engine? (yes, that was dumb, but I only had a short run it had to make)
2. No, most consumer OBD II scanners won't work on OBD I.
3. You dont know if it's the manifold gasket, or one or both the head gaskets at the moment.
4. Intake gasket is easier, since if head gasket, it comes off anyhow.
June 29th, 2019, 7:01 AM
#3
CF Beginner
Thread Starter
1. Had anti-freeze coolant? Drop motor oil now. Send to lab for report.
2. No, most consumer OBD II scanners won't work on OBD I.
3. You dont know if it's the manifold gasket, or one or both the head gaskets at the moment.
4. Intake gasket is easier, since if head gasket, it comes off anyhow.
2. No, most consumer OBD II scanners won't work on OBD I.
3. You dont know if it's the manifold gasket, or one or both the head gaskets at the moment.
4. Intake gasket is easier, since if head gasket, it comes off anyhow.
Problem did turn out to be intake manifold gaskets blown on both banks. Unfortunately, some sensors that take care of gauges were aged beyond their useful life on reassembly and had to be replaced. Then there was a problem getting timing right (excessive ping), but some rework by the mechanic has baby running great again. There was no apparent coolant in the oil but I will treat the truck to an oil change anyway. I replaced a damaged alternator and serpentine belt myself. Runs like a new truck!
Now if I can just get the "lazy start" fixed. Ever since I tore into the steering column a few years ago to fix Saginaw tilt column issue the start sequence is a challenge. Sometimes starter "hits" right away, other times I have to hit the clutch pedal to the floor hard, or (imagine this) pound hard on the steering wheel to get a start.I know I must have done something wrong in that tilt column repair but just don't know what to "fix" now. Guys and gals, if you've had this problem, share your knowledge, please.
July 7th, 2019, 10:14 AM
#4
CF Beginner
Thread Starter
I'd like to reopen this post. The problem I need to address is the failure of starter to engage when ignition key is used. To repeat and maybe clarify, the failure is not "always". Sometimes I can try and it engages and starts on first attempt. Other (Most) times nothing happens - no starter engage, no clicks, just silence and inactivity. Sometimes, pushing clutch in forcefully while holding key on works; sometimes pounding hard on bottom of tilt steering wheel will force an engage of starter, and this is the most common "working" remedy. All this says there is a failure to make an electrical connection that can sometimes be fixed by forcing steering column in.
My earlier post says "yes, I had the steering column apart to fix the Saginaw Wobble" but I don't know what I may have done wrong in reassembly. I park the truck on a grade in my driveway and since is has a five-speed I can roll start it. But when I want to use the truck, I have to leave the engine running at planned stops so I can be sure of it getting me back home. Someone told me there is a rod in the steering column that runs from the ignition switch to a contact at bottom of steering column, so I suppose that is why pounding hard on steering wheel may make the contact. But i dread taking column apart again to see if I can fix the problem, hoping that maybe there is some externally visible component that is really the problem.
A good friend has suggested that I just install an old-fashioned starter button switch on dash connected directly to right place (solenoid, starter, ....). Maybe that is the easiest solution. Other ideas, or other folks who have had the same problem and solved iit?
My earlier post says "yes, I had the steering column apart to fix the Saginaw Wobble" but I don't know what I may have done wrong in reassembly. I park the truck on a grade in my driveway and since is has a five-speed I can roll start it. But when I want to use the truck, I have to leave the engine running at planned stops so I can be sure of it getting me back home. Someone told me there is a rod in the steering column that runs from the ignition switch to a contact at bottom of steering column, so I suppose that is why pounding hard on steering wheel may make the contact. But i dread taking column apart again to see if I can fix the problem, hoping that maybe there is some externally visible component that is really the problem.
A good friend has suggested that I just install an old-fashioned starter button switch on dash connected directly to right place (solenoid, starter, ....). Maybe that is the easiest solution. Other ideas, or other folks who have had the same problem and solved iit?
July 9th, 2019, 8:18 AM
#5
CF Monarch
I'd like to reopen this post. The problem I need to address is the failure of starter to engage when ignition key is used. To repeat and maybe clarify, the failure is not "always". Sometimes I can try and it engages and starts on first attempt. Other (Most) times nothing happens - no starter engage, no clicks, just silence and inactivity. Sometimes, pushing clutch in forcefully while holding key on works; sometimes pounding hard on bottom of tilt steering wheel will force an engage of starter, and this is the most common "working" remedy. All this says there is a failure to make an electrical connection that can sometimes be fixed by forcing steering column in.
My earlier post says "yes, I had the steering column apart to fix the Saginaw Wobble" but I don't know what I may have done wrong in reassembly. I park the truck on a grade in my driveway and since is has a five-speed I can roll start it. But when I want to use the truck, I have to leave the engine running at planned stops so I can be sure of it getting me back home. Someone told me there is a rod in the steering column that runs from the ignition switch to a contact at bottom of steering column, so I suppose that is why pounding hard on steering wheel may make the contact. But i dread taking column apart again to see if I can fix the problem, hoping that maybe there is some externally visible component that is really the problem.
A good friend has suggested that I just install an old-fashioned starter button switch on dash connected directly to right place (solenoid, starter, ....). Maybe that is the easiest solution. Other ideas, or other folks who have had the same problem and solved iit?
My earlier post says "yes, I had the steering column apart to fix the Saginaw Wobble" but I don't know what I may have done wrong in reassembly. I park the truck on a grade in my driveway and since is has a five-speed I can roll start it. But when I want to use the truck, I have to leave the engine running at planned stops so I can be sure of it getting me back home. Someone told me there is a rod in the steering column that runs from the ignition switch to a contact at bottom of steering column, so I suppose that is why pounding hard on steering wheel may make the contact. But i dread taking column apart again to see if I can fix the problem, hoping that maybe there is some externally visible component that is really the problem.
A good friend has suggested that I just install an old-fashioned starter button switch on dash connected directly to right place (solenoid, starter, ....). Maybe that is the easiest solution. Other ideas, or other folks who have had the same problem and solved iit?
As to your steering column, yeap, those older Chevy pickup tilt-columns used to come loose as the bolts were not properly put in using something like Blue Locktight. Been there and done that. Made sure my K-1500 came with a solid column, in fact, just for that reason. I never needed a tilt column before in a pickup, but it would seem that Chevrolet has taken care of that issue on the newer model Chevy pickups.