Well, time for the next installment. Hope you guys don't mind these. They seem to be a bit on the "wordy" side, so if it is annoying, let me know. Sat. morning I finally found time to get the engine out of the back of my truck and start tearing into it. I was only going to get it on the stand for the day, but I thought about it and, seeing as how I am doing all this alone, I figured I really should pull the manifold off while I still had the hoist here. Of course, the hoist wouldn't reach to the ground so I had to remove the manifoold from the hoist and set it on the ground myself...MAN, you guys ain't kidding that they are heavy! But it was a lot easier to lift it when it was only 8 inches off the ground rather than 3 feet! Well, since I was that far, I figured, I would pull the pan too. Got it off and found all sorts of CHUNKS of stuff in the pan!!! Scared me to death, so I figured I better pull the heads and see if there were any valves left in them! Heads came off fairly easy, but those bolts really are TIGHT, aren't they?! Remember, this is my first time tearing into anything bigger that a Yamaha 400 bike motor. Anyway, the heads don't look too bad...a little flaky carbon buildup on the valves, but nothing looked too bad. Any clues what causes that? And is it a bad sign? Finally got to measure the stroke and sure enough, it is a true 390! Woohoo! And, as far as I can tell(no real good measuring device....tape measure), the bore seems to still be 4.05. As in, I don't think this motor has ever been touched! And let me tell you, I am amazed, because the cylinder walls seem perfect! No scoring, no scratches, nothing but smooth surface! A little discoloration in #4, but other than that, it appears to be in really good shape! And VERY little ridge at the tops of the cylinders. Oh yea, the plugs all looked real good too. Same color on all of them...nothing out of the ordinary. Anyway, that is about as far as I have gotten. I still have the cam, crank and pistons to pull, but that should go fairly easily. I did learn one very important thing though....pull the flywheel before putting it on the stand!!!! Fortunately, I still had the hoist when I realized this, so it wasn't too big of a deal to just hang it from the hoist again. Whew!! Anyway, hope you enjoy my little narratives, and I sure hope I am not boring you veterans who have done this sort of thing many times. Until next time....gotta go get greasy!!! Yea!! Oh BTW, the "chunks" appear to be nylon or plastic, so I am guessing they blew a timing gear somewhere along the way. At least I hope that is what it was! Any other guesses??


Chad Burns
1968 F-250 390 2v auto
Aurora, Co.

 

Sounds like you found a pearl! I know it is tempting to bore over for power purposes, but if there is any chance of only honing those cylinders, then you could get one more rebuild on it down the road? Something to consider, since there is a limited supply of blocks.


Tery

 

I was kind of thinking along the same lines. Since I think this engine will go into the truck I have now, I don't think I need to build for "Killer" power. A nice running engine should be all I need(he said with a straight face). Hmm, let's see, 32 years between rebuilds....this motor might be around for a long long time!

Chad Burns
1968 F-250 390 2v auto
Aurora, CO.

 

No plastic inside of the old FE sorry. The timing gears are made o metal. You might have found some silicon from a gasket oor something. The carbon buildup on the valves is completely normal if its just a few flakes. You can clean these with a rotary wire brush on the end of your drill. So far it sounds like you have a nice FE to start with. We don't mind these kind of posts either.

 

I'm actually enjoying the ongoing story.

 

O.k., now you really got me worried Rat. Simply because I found the exact same stuff in the oil pan of my current motor when I pulled the pan to change an oil pump last year. These chunks, and when I say chunks I mean 1/4" x 1/4" solid, really do appear to be like nylon or something. Were the original timing gears plastic? I swear to ya...these are pieces of plastic! Timing gears are the only thing I can possibly think of. If that isn't what it is, then what else could it possibly be????? Seems very strange! Thanks, and I guess I will continue the saga of The Junkyard Engine!

Chad Burns
1968 F-250 390 2v auto
Aurora, Co.

 

Plastic Timing gears started being used on 4bangers and later six cyl.. and now the v8's but back when that 390 was produced, no plastic or nylon was used. If there isnt any damage on the crank, rods, and pistons, I wouldnt worry about it much. Enjoying the Saga, keep it coming!

 

You guys are all wrong they did use the plastic cam gears ...the plastic was impregnated over the steel . this was done to queit the timing set . these sets were used through out the 60's and 70 to the present ...so everyone who is worryed do be its normal for these teeth to crack and fall off due to heat and normal wear.
Jon

 

I havve never seen that. My engine was a 74 -76 and the timing gears were all metal. That is interesting though. You are positive? Come to think of it my buddies 352 from his 65 truck was all metal and the 390 from the 66 he dropped in was all metal too.

 

This quat is right out of the FE book by Steve Christ " Some FE engines use camshaft sprockets with nylon teeth. These work well unless the engine is subject to exhtreem heat . If it is install a cast iron sprocket." Further on in the lower pragraph he states " In fact, the first nylon-tooth cam sprockets for big -blocks were introduced on the 427." I dont doubt this mans knowlege nore my own . He also states that " Nylon tooth sprockets absorb heavy shock loads, so they are gaining popularity in drag and NASCAR racing." This information can be found in the book on page 96 in the lower left hand corner
Hope this helps Jon

 

Chad,

Welcome to the wonderful world of FE's. Do you have a copy of Steve Christ's book "How to build a Big Block"? You really should consider it.

Don't forget to keep up with the locations of all the parts you take off. Like main bearing caps, push rods, etc. These items must go back in there original location. I also keep track of the connecting rod bearing caps.

Good luck,

 

I didn't bring my book to Korea with me but I believe you. Thats good news for chad. And yes Chad you should really get that book before going to far with your first FE.

 

Chad,
If it looks like a duck and quacks like a duck.....
I have seen plastic timing gears in FE's. I forget what year(s) exactly but mid to late 60's come to mind. One was in a 4x4 that was still running with no nylon left on the top gear except for a chunk about 1 1/2" long. This was in the early '70's so I'm sure it was original.
Looks like you found a sweet one. Congrats.
Greg

 

O.k., now I am really anxious to get the timing chain cover off! It will be interesting to see if there are steel gears in there or what. I will relax a bit though after reading that quote from Steve's book. Which, BTW, is on order and should be here this week. I'll let you all know what I find when I get a chance to get the cover off. Temps here in Co. just dropped from 70 on Sat. to low 30's on Sunday, so I may have to get a heater out in the garage in order to continue working on this thing. Stayed tuned for the next installment in the saga......the search for a 2nd job to pay for all this fun! Oh and Lee, you'd be proud of me man. I have every nut and bolt in their own ziploc baggies labeled with a Sharpie as to where they go. And pushrods are in the cardboard all labeled up. I was thiinking maybe an egg carton for all bearings, lifters and such. Good idea? And do I need to worry about which side the rocker arm assemblies are from?

Chad Burns
1968 F-250 390 2v auto
Aurora, CO.

 

A trick I use is to get a bucket and everything you were considering throwing away immediatly, put it in the bucket. I even save the old gaskets. You can always take out the trash when the engine is up and running. Take a center punch and put one mark on the front main cap, and two marks on the number two cap. Take your time removing the caps, especially number 5. Using the center punch put a mark on the crankshaft and the heads and block. This will help insure you get your stuff back from the machine shop. Removing the pistons requires removing the ridge at the top of the cylinder or you risk damaging the pistons. Put a piece of rubber hose on the rod bolts when you remove or install them to avoid nicking the crank. Take all the parts to the machine shop at the same time. Some times you will get away with honig the cylinders and installing new rings on your original pistons. Save all the bearings for indicators of bent rods, oil starvation and general indicators for engine wear. Those chunks you found in the pan could be valve stem seals. Not to worry! Post the part numbers of the heads, intake, crank, rods and block. Keep the info coming we "Bench Racers" love a good engine story!
William in Atlanta