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As some of you know, yesterday was dyno day and DT ended up with 290 RWHP.

I then drove it home for 2 hours in stop and go rush hour traffic, the temp never went above half on a stantand 65 gauge.

So today I think I will run out and get some gas.

I fire it up and I thought I heard a knock in the motor when it started.....but nothing at idle....so I drive to gas station, fill up, and drive home. Get on the gas a little near the house and the car tacs right up and feel good......step on the brake and the oil lights comes on bright. I tap the gas and the light goes off.

So here I am...sitting at a stop sign.....at 900 RPM the oil lights is on and there is a very deep knocking sound, not high pitched knocking, but very deep almost inaudible but you can feel it in your feet....tack up to 1000 and the oil light goes out and no sound.

So I am I guess slightly worried.


First thing I am going to do is change the oil since we really beat on in on the dyno.

There is no unusuall smoking coming from the car when driving, the rad is full, the oil is full on the dipstick.

So I am looking for ideas what this might be foreshadowing.

Will a simple oil change fix it, thinking that maybe the oil lost a lot of viscosity during dyno running.

Some other items of note, I ordered a new radiator, but the car is sitting in the garage now, and I can here coolant bubbling off in the overflow, I think the 7lb cap I am running may be too weak so now I am worried if that might have done anything.
 

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I hope it is something minor..but doesn't sound good..If I remember correctly you were winding that puppy to 7100 :: and I was thinking ouch..I have my rev limiter at 6200, as I have nothing much left after that anyway..As you probably know that sounds like a classic bearing issue..Time to hook up the master oil gauge.
blkstlln
 

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I hope that Cleveland is OK....

If problems persist, consider tearing into it soon to minimize costs of repair.
 

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I would not bother changing the oil. I'd go straight to pulling the pan and checking things out.

I know, not fun, but a deep knock is mains, and that is not a happy thing.
 

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Stock pan, 5 quarts is marginal when you're buzzing a motor to 7100RPM... Hope you weren't a quart low.....

Cut the oil filter apart, stretch out the paper, see what's trapped in there....
 

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I would save the fresh oil, and pull the engine. You are going to need to mike the main and rod journals, while you check out all of the other components. If you're lucky, it will only cost you a set of bearings and a full gasket set (not counting a lot of labor ::).

I wouldn't run it any more until repairs are made. Running it in this condition will only add to the repair bill.

Good luck, and keep smiling!
 

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To add to Art's post , cut a section of the filter paper out and keep it in it's original state without stretching the folds open . Wrap it in a shop towel or a wad of paper towels and wrap it up tight , but without opening the folds . Take the assembly and put it in a vise (if you have one) with the paper lined up so you will smash the folds tighter together (but still inline , not smashing the folds flat as that viods the purpose :)
Once you smah it in the vise , give it a minute or 2 and watch as it forces the oil in the paper out , leaving behind only whats left over (particles can't flow out through the paper holes :) )
Loosen the vise and carefully unwrap the paper , when you stretch it out you will have a clean clear view of the bunnies inside your lube system .
 

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Dodge,
Something not good is happening. The oil light as you know is due to low pressure. With a knock, odds are the oil that comes out of it will have bearing material in it. Like the other said, if you see a hint of metallic in the oil, dont even waste the oil. Oil wont lose its viscosity on a dyno, unless you flood the crap out of it with gas or something, like a physical leak of fuel. Odds are you broke something, we have all done it

Fresh motors blow up, bad stuff happens. Fresh bearings, if they are on the tight side of clearances generate an AMAZING amount of heat. However, it can be saved if you stop now. Odds are, if you pull the crank, turn it and drop it back in with new bearings and possibly an oil pump odds are it'll be fine.

Couple of questions when you built it.

Was it align-bored or align-honed?
Do you know the clearances of the rods and mains when it was assembled?
 

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yikes, was that really 7100 rpms? i don't think i've hit 6 grand yet on a fairly new engine... I blew an engine once before and i'll be damned if i do it again...
 

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I only see 6200 rpm on the sheet. http://users.zoominternet.net/~dodgeram/dynoresults.jpg

Mine was at 7200 rpm and this was pull number 20.
http://www.mustangmods.com/data/85/dyno_428hp_final_pull.jpg800x600.jpg
With the good rods you have in your engine it shouldn't matter. I agree though, don't run it any more. Sorry to hear. RAY
 

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Exactly what happened to Lottie's old motor... :/

Good luck Nick!
 

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If that's the case, it woudl be good to see some pictures of the damage so that DT would have something to go on to see on his engine...

willing to show us some pictures now of your "351W" that was horked? hmmmm?
 

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oy vei, i guess running it up to 7100 wasnt such a great idea ....probably an issue with the bottom end if its a deep sounding knock ....good luck
 
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