Thread: first run after rebuild

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Originally Posted by shawnlee28

Also cant you look at the spark plugs for little metal fragments,with a magnifier glass and see the rusults of detonation,or does that take miles and miles ?

You won't see that until the pistons begin to disassemble themselves and he may not have run the motor hard enough to get there yet.

11 to 1 CR, I thought 10 to 1 was as high as you wanted to go with iron heads and 10.5 with Al heads!!

okay...here's a clip:

http://www.youtube.com/watch?v=acj65xkSZgo

I think the very last 5 seconds are the most clear on what I mean...if there's any thing else to be heard, tell me!

Originally Posted by chevydriving

11 to 1 CR, I thought 10 to 1 was as high as you wanted to go with iron heads and 10.5 with Al heads!!

10.5 to 1 CR was the original stock CR for the '66 390 "special V8" available for the T-bird...
by the way...don't forget...we run 95 oct unleaded here in the EU

I would bet that a rod is hitting your crank scraper. It would sound different than that if it were a bad bearing. Pull out the scraper and try running it again.

Originally Posted by chevydriving

11 to 1 CR, I thought 10 to 1 was as high as you wanted to go with iron heads and 10.5 with Al heads!!

i use old chevy iron's at 12:5-1 hell the chevy 302's came with 11-1 and the ls6 came with 11-1 if i remeber right. 10.5 11-1 is the rule for pump gas.........

Definatly in the internals,I personally have never heard a crank scraper with clearance issues make noise ,that could be it.Worth a try.I would run it as little as possible untill the noise is figured out,nothing had self destructed yet and thats good.A main bearing{crank} has more of a deep knock sound and a little slower.It sounds kind of like a rod bearing or 2.I say kind of? Do you have roller rockers ,they could be hitting the valve covers ,but thats remote ,because you could locate that sound very easily and would sound diff.A very remote chance is the noise is timing sprocket/cam related{something loose} I hate to say this.....but I think its time to start taking things apart if the crank scraper removal does not cure this.
Some of the other guys should chime in soon.I would wait to hear from them before making a final decision.
The less run time the better ,because you could start pumping metal shavings thru the engine or break things.

Tommie, doesn't sound like the bottom end to me, pull the valve covers and
make sure the rockers are oiling. One rocker stand on each side has the
hole it to oil the shaft. It sounded like a squeek when you killed the engine.
At least that's easy to check out
good luck, Ron

Check what shoprat said.Piston in back wards ? Do these motors have ofset piston pins ?Piston slap noise ?I let a couple people I know listen to it that have owned these motors and they seem to thing its rotating assembly related.On a side note everyone said it is in rythym with the exaust note. I would wait to hear from Pat ,Denny or tech and some other engine guys on this. 1 person also said it sounds in time with the lifter motion ,these motors have rocker shafts correct ?I have no exsperiance with rocker shaft noise..The sound alone sounds almost like a rod bearing,...but the timing of the noise does not seem right for a rod,seems too fast for a main bearing and not quite the right sound for a cam /lifter prob. There may be little nuances that the recording device is not picking up making it more difficult to pin down.But I think no matter what your going to have to tear it down and check things.It just would be nice to have a certain piece to check ,rather than just having to check everything.It does sound exactly in time with the valve train and I also hear the squeak on shut down.

I am not a Ford guy but that sure sounds like rockers or lifters It seems to be to fast for bottom end. Maybe colapsing springs all the way???

I do have to admit that the noise sounds to be valve related. I used roller rockers indeed (the comp.cam type) these have a little larger ratio. The head wasn't milled, so I used the stock lenght pushrods. The heads were done by some-one else, before I had them shipped overhere. They used the stock valves, but some springs from a brand, called Isky...that's all I now. The camshaft itself is a clevite RV-torque cam and I wouldn't call this a wild grind! I did however, narrowed the oilsupply to the rockers (as mentioned in some books as a pressure bleed-off point). The valvecovers are defenitly coming of, cause if it's coming from there, it's either oilstarvation because of a too narrow supplyline, the earlier mentioned bottomming of the springs or otherwise related to the valvetrain...
Pistons are custom made to fit, only one set of eyebrows (wich are in mirror image for a set of 4 pistons, so they only fit one way) and yes, I found that out after putting some in, the wrong way, so I can assure you, they are in as they should be now!
Connectionrods are in the right way, yes, I made that mistake with the first try also already! No ofset pins and the top-end of the rods were narrowed down to fit the between the pintowers. 1mm space left instead of 3 mm stock.
I agree on the fact that the noise sounds to be continues and highpitched, wich would eliminate bottom end noise (besides a bearing or more), the fact that I doubt a loose bottomend part is because of the tightness of the completed engine; only the high-torque starter was able to rotate the thing!(just see how it stops instantly, when I shut of the power, I mean instantly, not even a half turn further!)

well, keep the suggestions coming! i'll check the darn thing (or myself, since i build it) either by the end of this week or the next, depending on my, eh, regular life...
It's great to see how many people are actually taking serious interest in helping me solve this! thanx! (guess I didn't sign up for nottin', now did I? ;-)

Did you use a feeler gauge to check for coil bind on the valve springs when you assembled the motor?

No...
it's the one thing i hoped would match up, even though it wasn't purchased as a matching set...
guess I have indications now, that it doesn't!

okay...first checkup;
flywheel and starter are clean...
next where the valvecovers;
oil present, but not too much, so the restriction works and the valvetrain is still getting oil.

Those Isky Valve springs are probably ISK-3605-D with seat pressure of 110 lbs and open pressure of 300 lbs.
according to specs, they shouldn't coilbind, with the lift i have (486 int and 512 exh), for the exh., there's little room left though!

something else i noticed though;

checking the lifters for presence of oil (by looking down the pushrods, wich seem to be just fine) I noticed that from back to front there's lesser and lesser oil to be seen at the top of the lifter and the last 2 look dry-ish...on each side...
since the engine didn't run for over 4 days now, this could be natural, but i was expecting to find at least some oil to stay in place...besides the obvious thought of a blocked oilpassage, i was thinking about lifters bottoming out!

a valve at open position, coming .150" short of theoretical hight...but no oil visible at the lifter topside, wich starts me questioning; If it did bleed out, during standstill, i should see SOMETHING!

back to the noise-indication...lifters are quite deep inside the block, so the rattle can be heard everywhere, being hard to pinpoint...
It keeps rythm with the valves/exhaust noise...

opinions, please...

I remember reading somewhere the hot tip back in the day for racing gurus was to put a solid lift cam in these ,take the lifters apart and just use the springs inside the lifter and adjust these like a solid ,the logic behind this was that the FE has some sort of oiling difference so it does not need to pump oil thru the lifters up the pushrod ,it gets from another source?They did as to "skate" around the rules for a hydro cam ,the tech would push down on the lifter and you would get movement like a hydro,but it was actually a solid cam with the modofied lifters set with a large lash......So the FE has some special oiling compared to other engines....

Point being, you can turn the engine over with the coil wire off and see if theres oil,if none ,try to start the engine and let it run for 30 sec to minute to visually confirm oil and look for anything out of the norm.