Johnny Boost

Ok I finished rebuilding my engine got it back in the car put everything back on it. found TDC got the timing good enough to get it to fire... and now I'm having issues.

I'm hearing a high pitch squeal coming from the engine.

At first I thought it was a belt slipping then maybe a pump or alternator... so I disconnected everything and the squeal is still there also I thought maybe there was some issue with the MOP but I disconnected that from the carb... running a Holley 550 cmf carb.

Any ideas what it could be?

I Replaced all four engine bearings when I rebuilt it...

Also my water pump was spinning smoothly and no noise or anything from it before I put it in the car but now the water pump is quite warm.

I'm really stumped.

In review it's NOT:
A Belt
AC Pump
Water Pump
Alternator
Metering Oil Pump
Fan Clutch
Air Pump was removed...

mazdaverx713b

iTrader: (91)

thats a real stupmer....does it possibly sound like a rubbing..metal to metal?

Johnny Boost

No not really At first I thought it might be the bearig in the alternator... but no it wasn't

rotordave

iTrader: (1)

Does it happen throughout the rev range?

Johnny Boost

I dunno... Being I just rebuilt it, I haven't had a chance to break it in yet because of the squeal and the fact it dies unless I give it gas just before it dies.

My friend came over and listened to it... she thinks it's external and sounds like air being sucked in or blown out.

I just replaced the belts tonight to help make sure that wasn't the cause and changed out the fuel filter.

trochoid

iTrader: (6)

Some vacuum leaks can sound like a squeal. Other option is how's the oil pressure? Better hope it's a vacuum leak.

Johnny Boost

I have no gauge to check for oil presure. Before I rebuilt the engine the oil presure was real good...

I'll check for vacuum leaks tomorrow or tuesday

If it is oil related what might I be looking for? Do you think it's to high of presure or to low. The oil cooler lines are leaking and the front cover in one spot but they started leaking prior to getting the engine to fire up.

trochoid

iTrader: (6)

My biggest concern is a fault in the oiling system and it's the main bearings that are squealing. If you have oil pressure, then it's most likely a vacuum leak that you'll need to find by squirting a liquid around until you find it. Use an aerosol can that has a straw, it can be brake cleaner, carb cleaner, sometimes even water works.

Sounds like your friend has better hearing, let her find it. There are some frequencies of vacuum leaks that I can't hear, but a friend of mine can. He found 3 small leaks on my FC when I couldn't hear any of them.

Johnny Boost

The car would die every time I'd get out to go check for it. So the one time she was there she could pin point it a little better.
If the oil filter has oil in it is that a sign of having oil pressure? I would think so but I'm still learning.
I'll check for vacuum leaks once I get my paper finished...

2GSLSE

iTrader: (6)

is there any possability that the thrust bearings/spacer isn't installed correctly when putting the front back together? did you check to see if you has any end play or just throw it together?

Johnny Boost

No end play at all. I was rather careful to place it back together correctly so nothing would happen...

The only thing I can think off is that I had to remove the 10 MM bolt a few times and although I was careful I wonder could that coper washer have been damaged and be the cause of the squeal?

It doesn't sound like metal on metal but then again I'm not sure. The tone also changes with the amount of throttle given. Almost sounds like turbo spool... but there isn't any turbo to spool.

Johnny Boost

Ok well I found the squeal.

It's sucking in air and leaking gas out of the manifold. Evidently the gasket isn't sealing so I ordered new intake gasket from mazdatrix.

I used my mothers stethoscope to locate the source of the squeal. When I put my hand by the corner of the intake mani I could feel the air sucking in. So I'll replace the gasket and then I'll update one more time to make sure that fixed it.

DivinDriver

iTrader: (15)

You know, you're supposed to have some end play, per spec. Without it, things rub as parts heat up. No end play at all is very expensive later.

This is spec for a 80 12a:



I did a rebuild without sufficient end-play two engines ago; cost me a complete rebuild eventually.

Johnny Boost

End play as in horizontal movement... I didn't measure but there is some. I thought End play was a side to side up and down sort of thing.

DivinDriver

iTrader: (15)

Usually, the "side to side" or "wobble" motion is called "runout." Like when you check your brake discs: motion along the axle is "end play," motion at right angles to the axle is "runout."

Johnny Boost

Good to know thanks!