My '83 302 is coming up on 175K and I am wondering if there is anything I need to be doing as preventative maintenance to keep it going. I change the oil every 5K. Plugs, filters, etc changed regularly. The engine is stock and runs fine. Oil pressure is fine... I think... at idle when warm it is about 8-10 psi... has been for years.

What about the timing chain? In my OHC cars, the timing belt would have to be changed every 75k of so.

 

As for oil changes I would change it more often if you drive in town more often. 5k is a long space between oil changes, I would do it no later than every 3k. 8-10 psi, it should be at least 30 psi warm! That is very low, but not surprising for a 302 because every high mileage 302 I have ever seen gets low oil pressure when it gets hot. For some reason those motors can still go a long time on low oil pressure. I would try running a heavier weight oil in it. I have heard good results from running Valvoline Maxlife in higher mileage engines. I run regular 10w30 Valvoline in my truck but I only have about 40k on the rebuild. My buddy runs Maxlife in his high mileage 95 S10 and it certainly has made a difference in how smooth it runs and it gets better oil pressure too. I change plugs, wires, cap, rotor every 6 months or so. I change fuel filters every 3 months, and air filters when they need it. Best way to get a lot of life out of an old truck is to take as best care of it as you can, keep it tuned up, use good quality motor oil, don't beat up on it too hard, and take it out on the highway to clear it out occasionally if you don't drive in out of town very much. If you plan on keeping the truck for a while I would start saving for a rebuild because, it will probably need it pretty soon. That's just my 2 cents! Good luck!

 

As for the timing chain, I would'nt worry about it until you start to have performance problems. Keep an eye on it, when it goes I would plan on just going though the whole engine with a total rebuild. This is why I would suggest starting to set some money aside for a rebuild, so you will be ready for it when it comes. If you rebuild it yourself, you should be able to rebuild it for 500 to 1000 dollars depending on how much machining needs to be done on the block, heads, crank, camshaft, etc. There is really no telling when a motor with a lot of miles on it is going to need to be overhauled. Just take the best care of it you can and be ready for it when it happens. It may run for another 100k...it may run for another 25k. There really is no way of telling. That is my best recommendation.

 

Good advice, not only that, but lubication is a neccessary means of keeping the joints lubed and making sure those wheel bearing are serviced regularly useing Lithum Grease for wheel bearing, every 6 months or less is good about the time to check those by seeing if you have any wobble while its up getting the oil change....and the rear diff. needs to be checked along with the cooling system for leaks...preventive care goes a long way in keeping the truck off the side of the highway....no body needs that kind of engine trouble.

 

That's a beautiful 83 you got there! I wish my 84 was that clean! I noticed the speedometer reads in KM/H, that's really neat I have never seen such a thing before! It looks as though it has been very well cared for!

 

Thanks for the advice all. The low oil pressure is a concern but since it is working fine right now so I don't want to mess with it.

About the timing chain mentioned adove, how does one know when it is coing bad? What are the signs.

Pkupman82 has a sharp eye... the truck is Canadian so it has a kilometers per hour speedo. I am the secon owner of the truck. I have had it 6 years and is my daily driver. Bought it from a 77 year old gentleman farmer who used it at a farm truck for all tose years. It had 74k on it then. The paint was faded but little rust. It was filled with muliple dents and dings from farm use. I just painted it, re-covered the seats and head liner... that was it. The truck was straight stock and needed only the ususal mechanical repairs... exhaust, tires, brakes rear axle seals, tune-up, etc.

 

You have done very well with your 83, my 84 was built at the Ontario Plant. I guess mine would be concidered Canadian too, but it has the regular mph speedometer. It sounds as though your pickup was optioned pretty well to, mine is just a basic model F150. Options included: Power steering, Power brakes, AM radio, Heavy Duty 4 speed grannybox transmission, and 4 wheel drive. Of course since then I have added a few goodies to make it better fit my needs. As for your timing chain, you will start to notice the engine does not run smooth, it may be down on power, and it may not want to hold idle speed. You could also experience dieseling and or backfiring. When a timing chain wears, it stretches and can cause the engine to slip out of time. In extreme cases, the chain can actually jump teeth on the timing gears. One reason why I do not recommend installing a new timing chain on a higher mileage engine is, it can put a lot of stress on the cam bearings; causing them to wear out faster. My buddy and I found this out the hard way after replacing the timing chain on his 79 Plymouth Trailduster 4x4 318 2bbl. To add to that, and you may not know this, but nearly all of the oil pressure relies on the cam bearings, if they wear out you will have no oil pressure and the engine will eventually start to break itself down. 302s and 351 Windsors are notorious for not holding oil pressure once they get up in mileage. As I understand it, the cam bearings are the culprit for this problem on these engines. It is very possible you will be looking at needing a rebuild pretty soon, my recommendation would be to no get too rough with it and it should be okay for a little while longer. I am not entirely sure how long it will run for though. That is a beautiful truck, if it were mine I would definately spend the money on a good quality rebuild. It will pay for itself in the end, with years of reliable service. I rebuilt the 300 six in my 84 and since then it has been a great driver with plenty of power and good gas mileage. If you plan on hanging on to the truck for a while, it will be a worth while investment. Good luck!

 

I agree with the worn cam bearings being the culprite for low oil pressure, but as long as oil is still making it to the top of the engine these things can soldier on for a long time. A brother of mine had an old 400 that would have oil pressure reading in the middle of the normal range when he started the truck and it would drop off to near "0" after it got good and warm. He added a new guage thinking the factory one couldn't be right. Then he KNEW its almost "0" after it got warm. Ran that way for over 30K before he traded the truck. Figured he couldn't be hurting it anymore then it already was.

The stretched timing chain will lead to missing and other timing related problems. A new (correct size) timing chain and gears are going to cause less wear to cam bearings then a worn out set that whips and loads up due to slack.

 

After a while with low oil pressure...that cam lobe will get lower an lower an lower...till its nothing...then your valve won't open...then Mr.Backfire will destroy that piston with Mrs Rod visting the oil pan for a bath...hummm, think I've been up too long.