trenolds39

I just finished replacing the front main seal that was leaking on my 1992 toyota pickup, and have noticed a high pitched whine from the engine, specifically under load. It is most noticeable when I rev the engine to ~3k then shift up, but it doesn't sound like typical squeal or chirping that belts make. When replacing the front seal, I used the thinner seal so it wouldn't ride in the tiny groove I had in my crankshaft pulley. I should also mention that I used the starter method and it took 10-12 bumps to break the pulley bolt loose. I also pulled the oil pump and replaced the O-ring and put assembly lube in between the gears before reinstalling. I used all purpose grease on the inner lip of the main seal, and had no issues reseating it. I noticed the drive spline on the oil pump had grooves on the smooth part of the spline (non toothed part?), but I didn't think much of it at the time.

My old drive belt was worn out,so I replaced it with a Duralast 15345 v belt from autozone. The only difference is my old Dayco belt had the cogs on the outer part of the belt that doesn't ride in the pulley, and this Duralast belt has the cogs on the inside where it rides in the pulley. I loosened the alternator and used a breaker bar between the block and the alternator to try and push it out to tension the belt while I locked it down. I think it has similar tension to the old belt, which didn't make any noises like this. I have somewhere between 1/4" to 3/8" of deflection in the belt, I have no way to accurately measure the tension. Since I had never changed a drive belt before and the FSM/Haynes manual doesn't say much, I didn't think to clean the pulley surfaces or do anything other than swap the belt and tension it. My only other concern is that I pulled the fan clutch and pulley to get the crankshaft bolt loose, so when reinstalling I just put the nuts on the studs coming from the water pump at finger tight, then tried to snug them down after tensioning the belt. So it's possible that the water pump pulley is not totally aligned, I'm just not sure how to check that.

I had my timing chain replaced 30k ago, and when I did my valves ~3k ago I saw the timing chain guides were still intact. I don't know that anything involving the main seal could be making this whining noise, so I either knocked something else loose/broke something trying to get the pulley bolt loose, or there's something wrong with the belt or pulleys. I might just be paranoid and looking for something wrong and this could just be normal engine noise, but I don't remember it making this whining sound.

Based on what I've read elsewhere, I think this is caused by the cogs on the new belt. Should I go get an OEM belt? Any advice would be appreciated.

75w90mantraN

Sounds ok to me. You can go OEM for peace of mind, just differences in quality and manufacture. Whenever I go non-OEM, I try to read up on how successful the part is and make my decision based on that. Just make sure the fan clutch and everything is all tightened to spec.

As long as the main seal isn't leaking oil, you should be good there.

Good work by the way.

trenolds39

I drove it around and the next day it wasn't making that high pitched noise. Must've been a break in or seating thing. Regardless, I did pick up an OEM belt from the dealership in case I want to swap it. I was planning on retightening this belt after 100 miles and noticed it has a slight bounce on the run between the crankshaft and water pump. I tensioned it based on the run between the pump and alternator and later realized that it wasn't the longest section. So either it is doing this because it is slightly loose, or just a result of the cogs on the inside. For attaching the fan clutch to the pulley, I wasn't sure how to torque them so I just put the truck in 5th and tried to snug them all down the best I could. There isn't much room to work between the fan clutch and pulley, but hopefully the flange nuts will keep it tight. Been keeping an eye on the crankshaft and haven't seen any leaks yet, although I haven't had a chance to drive it on the highway to really test it out.

Before I realized it was the main seal that was leaking, I switched to 10W-40 to try and slow the leak. I live in CO, so I think I can run this weight year round without issues. Is the increase in oil pressure at temperature negligible, or could this exacerbate any potential leaks? It seems to run quieter, but that could be in my head.

75w90mantraN

This is the combination I came up with to torque a variety of fasteners in tight spaces. I used this successfully on the fan clutch pulley nuts. Ignore the sway bar in the photo.

As far as using 10w-40, I've only heard others' choice of using, personally I stick with 10w-30, but hey, if don't have driving issues, lights, oil pressure problems, then maybe you'll be fine. I don't know about long term use. It might slow down the leak, but it might not provide enough lubrication to the engine in colder temps/cold starts. Summertime is a safe way to go. It's a tossup really, so much subjective info for and against its use because it used to be the principle back in earlier decades, but as the technology changes, who knows if the advice still holds true. To each his own. I try to fix whatever is causing the leak, but if your oil pressure warning lights up, it's definitely a short-term solution. The engine may not leak, but it will for sure work harder to circulate and can use up more fuel, maybe even increase engine temps. The parts of the engine that are too small for the oil to lubricate (again subjective thought out there) could wear down and lead to problems later on. Why I can't support long term use. Don't mean to discourage you. If I were using 10w-40, I wouldn't put a lot of strain on the engine (high rpms). I think the concern of too high of oil pressure would be possible if you overfill the oil pan, use a drastically thicker viscosity and abuse the hell out of it, or your oil pump fails.
Here's a link so you can see how debatable it can get--
https://www.bobistheoilguy.com/forum...Number=1824839

I have an Accord that used to have annoying oil leaks in multiple places, but they were all slow and small, so I replaced a number of gaskets and even a VTEC switch known to leak and no worries on 10w-30.

I have a friend who does have low oil pressure problems in her import make and in her case, I can see why the qt of 10w-40 sits not far away from the driver seat. It's a band-aid to me. Not a long-term fix.

Again, my thoughts only. 92 is pretty good to keep running. So you're doing something right or else it wouldn't make it to 2017.