This is in regard to a 1994 Plymouth Sundance 4-cylinder 2.5L, which I am trying to restore. The original problem was a rod knocking on one cylinder, I pulled the engine and transmission due to the damaged crankshaft and external leakage of transmission fluid.
I was originally going to have a machine shop clean and repair this engine, but I’m not sure it makes sense to spend $900 in labor plus $300 in parts when I can get a guaranteed good used engine with less than 60,000 miles on it shipped to my door for $1300. Plus I have decided that I want to gain the experience and attempt to repair it myself (hopefully for a lot less money, too.)
I went to a junkyard that has a car with this engine, which was apparently totaled in an accident, and noticed that it had a recent head gasket replacement. I removed and bought the head, which appears to have been professionally resurfaced and was being used successfully with an MLS gasket. However, it is obvious to me that the valve stem seals are worn out, because there is a lot of oil/carbon buildup on the top of the valves and the valve stems. I also have the original head, which looks good, but presumably would need professional resurfacing if I want to use an MLS gasket. In either case, I’d probably want to replace the valve stem seals, and if I did that myself then I’d only have to pay about $100 for the resurfacing.
So my question is what specific tools should I buy in order to replace the valve stem seals, clean up the actual valves, and clean up the threads in the engine block? I.E. what specific valve spring compressor, what specific thread chasing tap, and what specific chemical or cleaning tool should I buy for this job? Any advice (other than to give up and junk the car) would be appreciated.
Yes, sir. I have the Chrysler factory service manuals, and also a Haynes book. The FSM references certain Chrysler special tools. I am looking for advice from people here who have done this type of work as to what tools they use (that are readily available, preferably online).
I understand your plan for the upper half of the engine, but how are you planning to address the damaged crankshaft and other lower engine parts? Purchase another used engine, and use the bottom half for the replacement engine? Or repair the crank and whatever else needs repair in the existing lower half of the original engine?
I have found that there are certain repair procedures that require machinery that’s really too expensive and too limited in use for me to own, and those jobs I pay someone to do. For me, with a small space in my garage to work, and very limited storage, it would not pay to buy the tools to do a proper valve job. I have found that if I take the head to an automotive machine shop the cost of the job, done properly, is not too much different than the cost of the tools. And how many valve jobs am I ever going to do?
A local junkyard which pulls the parts for you has this engine in stock now, but their policy is that engines over 15 years old are not tested, sold as a “rebuildable core” and the only guarantee is that the engine will turn freely. The complete engine costs $250 plus tax. It may run fine, but no way to really know without either installing it, or taking it apart and checking for damage such as evidence of overheating or obvious bearing play.
I can buy a remanufactured crankshaft online, which includes all of the main and rod bearings for that specific crankshaft. That costs $200 with free shipping. I think the connecting rod is still ok, but I could just as easily grab a used piston and connecting rod from an engine at a “you pull it” yard with similar miles.
New pistons are not expensive and a new rod won’t break any budget. Any valve spring compressor will work well. I don’t like the lever type. Carburetor cleaner will help and it removes paint from leather flight jackets, not suede. Don’t restore that car; get the small Charger from that era. All you gotta do is find one. Use an old piston ring to clean ring grooves.
Measure those mains and journals because mistakes are made and should always be eliminated. One undersized main and you will have low oil pressure.
Im confused as to what you are doing anymore. You want to restore a disposable automobile… that’s fine, to each his own I dont judge when it comes to these things as I have invested vast amounts of time an effort in similar things along the way to where I am now…all in the name of knowledge and all that.
So grab that 250 engine and install it and drive it. If you want to replace the valve stem seals then do so… You didn’t need to take the head off of it to do this procedure, but it seems you already made that mistake already.
imho you are vastly overthinking each and every step of this entire procedure, but that is ok so long as you dont go disassembling perfectly useable assemblies all in the name of “making it better”. You seem to be going overboard in strange areas.
Here is what I would have suggested… Buy the functional engine from the yard that had a new head gasket…install the engine and motor on…deal with any issues that arose when they arose down the road, so long as it runs and drives well…you are ahead of the game.
You could then play with your old engine at your leisure. Doing whatever you wanted to it in the name of learning and or playing around. Does this make any sense ?
Really depends on how much DIY you actually intend to do. You have the manual, good.
You need at least a decent caliper that can measure to 0.001 inch. And plastigage to confirm bearing clearances. And a set of snap gauges to measure inside bores to use with the caliper. Those ONLY tell you if you if the engine was re-bored or the crank ground under and how much. It is NOT adequate for bearing clearances… plastigage is. But you still need piston clearances so a set of feeler gauges is needed, too. I like the big C-clamp valve spring compressors but those can be obtained from free tool programs at the local auto parts store. You will need a harmonic balancer puller and likely a gear puller. A shop press is nice, too. 12 ton should do it. An engine stand is good for re-assembly. I know I am forgetting things and I don’t know this engine at all. This is based on the 3 different engine family rebuilds I’ve done. This will NOT remove the need for a machine shop so you WILL need a stack of $100 bills.
Good work is NOT cheap and cheap work is no good.
Edit: A good set of torque wrenches, sockets, extensions, prybars.
Snap gauges can be tricky for a novice. It’s easy to get them cocked and get bad readings so technique is important. The receiving inspection guys at work hate them for that reason. They want a robot arm. The mechanical engineers just shake their heads…
None of the machine shops I have ever used to do resurfacing or other head work would ever do it without completely disassembling the head first- and replacing things like valve seals while it is convenient to do so. So I wonder if it was professionally done…or just disc sanded…
I’ve rebuilt a few engines (but not very recently). I’d pull the heads and disassemble the block and then block, head(s) and crank to trusted machine shop. They’d go through the head and remove carbon buildup if any. Replace springs, sometimes rockers and mill smooth. The block they’d hone all the cylinder calls smooth. If any they need to make the cylinder walls larger they’d call me first. If OK, I’d usually then get the new pistons through them (easier to do it that way if there’s a problem). they’d also mill the head(s) and block smooth.
They’d check the crank also. If need be polish and maybe resize the bearings.
I’d clean the pistons and rods, and replace if needed.
With everything back from machine shop I’d assemble. Most of the machine shops I used had all the gaskets and bearings and piston rings. Easier and less change of a screw-up (mainly my screw-up).
Many machine shops would disassemble the block and put it all back together also. By doing it myself I saved easily 1/2 the price of full rebuild by them. Plus I could take my time and do it right.
If the block is really bad it might be worth getting a small-block.
So about the $250 engine, which is only guaranteed not to be seized. If I buy this, and take off the oil pan and there are no metal shavings/sludge/etc, and I attempt to wiggle the connecting rods and don’t notice any play, can I reasonably assume that the short block will run well, and just pay the machine shop to recondition my original head (about $300)?
Without pulling the Pistons you’ll never know the condition of the rings. And just because a rod doesn’t more - doesn’t mean there aren’t any problems with the bearings. You’re talking about an engine that’s over 20 years old. It may not be worth the time or money to fix it.
Your current crankshaft has been damaged and that means the journals will have to be ground undersized. If the damage is too great, that option will not be available. A reman crankshaft will probably already be ground undersized but maybe only 0.010". Can you get that spec before buying?
Since the junkyard engine has not sized, the crank is not likely to be damaged. Best case the journals are still in spec and you will only need new bushings. I’d probably go this route. But first i would check ebay. Sometimes a reman company will dump overstock engines pretty cheap. You might get a complete longblock for $500 or less.
I would not rework the heads if it shows signs of being reworked already. Use a quality large carpenters square to determine if the surface is flat before making that decision. You do not need to rework the head just to replace the valve stem seals.