Howdy,
I recently came into possession of a 1988 4x4 Pickup with a 22re. The engine runs but seems to have trouble picking up speed and has a slight slapping/knocking noise. I believe this to be the timing chain needing to be replaced, so that is definitely on the list. I also noticed a drip from the joint between the engine and transmission that also persists near the drain plug. Given that I'm going to have to drop the oil pan during the timing chain fix I'll be able to tell if the oil pan gasket has gone bad, but was wondering if perhaps the rear main seal may have gone as well. The engine leaks around the valve cover, which of course will be replaced in the timing chain job as well. I suspect that the engine has a bad case of blow-by as well and was wondering if there was a way to mitigate that problem, other than a full rebuild, while I had the engine apart to replace the timing chain.
I also wondered if there was a new alternative go-to part store now that engnbldr is out of the picture.

 

If you have a leak around the valve cover, you might want to check the rear halfmoon part of the valve cover gasket. That's a well known failure point. Or leaky point, if you prefer.

It's quite possible that a leak from the rear halfmoon, is flowing down the rear of the engine, causing the drip you see. Get a small inspection mirror on a telescoping rod, and a decent flashlight. Clean the area Thoroughlyand then watch around that rear halfmoon for leakage. You might be surprized.
Of course, it's entirely possible the rear main is, in fact, leaking. If so, obviously, you'll need to drop the transmission to get to it. May as well replace the clutch while you're there.

How do know about the blow-by? Are the spark plugs oily when you pull them out? Or is there white smoke coming from the exhaust?
If there's oil passing the rings into the cylinders, if that's what you mean, then yes, it's quite possible the rings will need to be replaced. And that means a bottom end rebuild. Probably the bearings on the piston rods, rings, and so on. I've never done a bottom end, so I am not sure what all's involved.
That means a head gasket replacement as well. I just recently saw in another thread that a complete rebuild gasket set is $136.00. I can't recall just where. If I find it again, I'll see where the source is. After all, these are 30+ year old trucks. Things do wear out, even on these wonderfully designed trucks.

The 22R engine, the basic portion of the 22R and 22RE, has a habit of having a valve knock. Not real loud, but very persistent. Even right after a valve adjustment, it's there.

I would do all the repair work as required, then check on this. Could be plugs, wires, distributor cap/rotor, valve adjustment, timing adjustment, TPS adjustment, O2 sensor...
You see? I would take care of the main troubles, and give it a good tune up, then see how the engine performs.

Finally, if it's been a few years since it was done last, you might consider changing out the brake fluid. Clutch brake fluid, too. It absorbs water from the atmosphere over time. All it takes is a good brake bleed. Just bleed the brakes in the normal order, and keep replacing the fluid as the reservoir runs low, until clean fluid comes from the brake you're bleeding, then onto the next one. Bleed that until clean fluid comes out, and so on. Don't forget the LPSV!
Same for the coolant, and it's associated hoses. At the very least, the three big ones. If it hasn't been done in few years, a good flush/fill is a good idea. Make sure you use the good, Toyota Red coolant, not the commercial green stuff. It's made just for these trucks.
Naturally, new belts are essential...
Same with all parts you replace. Go OEM every chance you get.

You're entering into a commitment to some work. Like I said, old trucks wear down over time, and if it hasn't been well maintained by the previous owner, you'll need to do some catch-up work. Once you get it going good, though, it's very rewarding. You'll see why we love these trucks so much
Pat☺

 

I could see this being true as most of the leak seems to be coming from near the rear of the valve cover.

There seems to be a bit of white smoke coming from the exhaust, yes. The plugs aren't soaked, but they aren't clean either. I considered just doing a new head gasket along with the other things to see if I could mitigate the problem. I don't want to commit to a full rebuild if I can solve some of the issues and get the engine running pretty well for a time. Money is a factor and I bought this truck as a weekend toy and wrench turning project. When all is said and done I would like to eventually do a complete overhaul of the whole truck one day when money permits. I don't really know a reliable machinist for a complete rebuild and would prefer to do as much of the work myself as possible.

Yes, it seems I did stumble into a fair bit of work. I did get the truck for dirt cheap though and the rest of it is in fairly good condition. The plan is to start with the few things I can see now, and see how it all ends up. Give her a tune up and hope for the best. Where do you usually source your parts from? 22re performance and LC Engineering both have some pretty good gasket sets/timing chain replacement kits. However I am not sure those are the best options. Some people laud their performance while others say its over priced.

One more thing I figured out while going through it is there may be a slight knocking coming from the exhaust. I noticed yesterday that the place where the headers meet the downpipe may be missing a bolt. I'm not positive but that could also be another source of distinct "knocking" sound. I'm also unsure of a place that sells specific 22re hardware as I discovered I'm also missing some castle nuts from the top of the valve cover. Their loss doesn't seem to be detrimental, but I'd like to replace them.

Thank you so much for the advice and information, Pat! I really do appreciate it and it was also a good welcome into the community on my very first post.

 

I'm no mechanic, by any stretch, but even I was able to replace the head gasket in my 4Runner fairly easily. For a GOOD mechanic, I understand it's a very easy project.
It's also a viable possibility for your oil intrusion problem. Check your oil for the presence of water, and your water for the presence of oil. A good check is to pull the oil filler cap, also known as the 710 cap (funny joke there), and look inside it for a "chocolate milkshake" sort of substance. That's a sure indication of a head gasket allowing water into the oil. Another check is the cylinder pressure check. You can get a pressure test kit from almost any auto parts store to do that.

You can check the head and block, when you pull the head to do the head gasket, for warpage. All you need is a decent metal ruler. IF either isn't within the FSM specs, though, you will need a good machine shop to make them properly flat. I got lucky when I did the head on my Runner, both the new head and the block were within spec.
Heck, the hardest part was getting all the old head gasket materiel off. I spent more time cleaning than wrenching.

Many people replace the bolts (and nuts) on the exhaust system when they do a head job. If you're not careful, they can shear pretty easily. Make sure you have a good easy-out set available. AND new thread-zerts to replace any damaged threads that might happen. I am pretty sure you can get all bolts and nuts you will need, other than head bolts from most hardware or auto parts stores. I don't know the exact hardness specs, but you can pretty easily match threads. I got a good tap n die set, and that made it easier to match nuts and bolts.

As to the "castle nuts" on the valve cover: Do you mean the 4 that hold the valve cover on? Those are supposed to be acorn nuts, actually. Be careful not to over-tighten them when putting them on! The nuts sometimes have trouble getting started on the bolts with a new valve cover gasket and the new grommets. I've found that by putting 3 of the 4 old ones on, and tightening them down, you can usually get the 4th to go in with the new grommet. Then do it with 2 to get the 3rd, and so on. If you do front one side, then back other side, and so on, it also makes it easier.

You get what you pay for. When it comes to timing chain and gasket sets, either 22Re performance, or LCE, are both good. However, Rock Auto is also a very good source for OEM parts, for very reasonable prices. You can be fairly certain you're getting OEM if it has a Japanese manufacturer's name. NGK, Denso, and so forth. Avoid Bosch like the plague. It's made for European cars. Why OEM over aftermarket? Just look how long the factory parts have lasted
Just so you know, and I've heard all different opinions on this, I used FelPro gasket sets when I did the head on my 4Runner, and it's still doing great. Well, it would be if it hadn't caught fire, but that's an entirely different "thing".
Another possible source is your local Toyota dealership. Last resort, as they tend to be over priced, but they are a source. Local Auto parts stores, too. Many do carry OEM parts for these trucks in stock.

When doing the tune-up, which may well improve a lot of things, make sure you do everything. Belts, radiator hoses and flush/fill, oil and filter, distributor cap and rotor, plug wires, plugs, PCV valve, and it's hoses, check ALL the vacuum lines, all of it. Set the valve lash, and replace the valve cover gasket as planned. Remember, you'll need a small amount of RTV to place the half-moons in. The FSM shows exactly where, and even specifies what kind to use. Maybe even consider changing the oil in the transmission and pumpkins, and lubing all the drive shaft U Joints.

Good luck, and have a lot of fun
Pat☺