Yeah, I know this isn’t a Mustang question, but considering this is an engine oil leak issue, I’m sure it’s applicable to most engines.
My 89 GMC pick-up, with 137,000 miles on it, has been leaking oil for a few years, though I’ve never been able to figure out where the leak is. I only put a few 1000 miles on it a year, so it wasn’t a big deal. I just check it every time I use it. A few weeks ago on the highway, on my way to Mustangs Unlimited to pick up new fenders, the serpentine belt slipped off the tensioner pulley. (Apparently NAPA lists the same pulley for the tensioner and the idler which I now know to be wrong. ) Not wanting to get stuck on the highway, I drove it for a few minutes to get off the exit and close to a phone. The coolant was bubbling out of the overflow tank as I stopped in the parking lot of the local fire station.
I had it towed home. Replaced the whole tensioner assembly this time, since that was the only way I could get the correct pulley. Changed the oil, filter, and coolant. No sings of coolant in the oil, nor oil in the coolant. It starts and runs like a champ, with a little more valve chatter than it had previously. Though I think overheating has caused the oil leak to get worse – at least I can now see where it’s coming from (sort of).
I saw smoke coming from around the exhaust manifold near the front right cylinder so I cleaned the area with some carb cleaner and took a closer look. The oil is visibly coming out, at that one cylinder, between the exhaust manifold and the head. It must be a pretty bad leak since I can see it ooze upward onto the head from the top of the exhaust manifold as soon as the engine is started. I’m sure new oil is helping the situation.
I could do a compression test, but am wondering if I wouldn’t just be wasting my time. I’m thinking it’s probably time to buy a rebuilt long block. What do you guys think?
Thanks
My 89 GMC pick-up, with 137,000 miles on it, has been leaking oil for a few years, though I’ve never been able to figure out where the leak is. I only put a few 1000 miles on it a year, so it wasn’t a big deal. I just check it every time I use it. A few weeks ago on the highway, on my way to Mustangs Unlimited to pick up new fenders, the serpentine belt slipped off the tensioner pulley. (Apparently NAPA lists the same pulley for the tensioner and the idler which I now know to be wrong. ) Not wanting to get stuck on the highway, I drove it for a few minutes to get off the exit and close to a phone. The coolant was bubbling out of the overflow tank as I stopped in the parking lot of the local fire station.
I had it towed home. Replaced the whole tensioner assembly this time, since that was the only way I could get the correct pulley. Changed the oil, filter, and coolant. No sings of coolant in the oil, nor oil in the coolant. It starts and runs like a champ, with a little more valve chatter than it had previously. Though I think overheating has caused the oil leak to get worse – at least I can now see where it’s coming from (sort of).
I saw smoke coming from around the exhaust manifold near the front right cylinder so I cleaned the area with some carb cleaner and took a closer look. The oil is visibly coming out, at that one cylinder, between the exhaust manifold and the head. It must be a pretty bad leak since I can see it ooze upward onto the head from the top of the exhaust manifold as soon as the engine is started. I’m sure new oil is helping the situation.
I could do a compression test, but am wondering if I wouldn’t just be wasting my time. I’m thinking it’s probably time to buy a rebuilt long block. What do you guys think?
Thanks