Noise on start up...
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Noise on start up...
[font size="1" color="#FF0000"]LAST EDITED ON 12-Jun-01 AT 11:09 AM (EST)[/font][p]I have 351 4 bbl motor in an 87 Bronco that has been making an occasional noise on warm start up. This motor was rebuilt about 10,000 miles ago (last October) and otherwise runs fine. The noise is sort of a deep, quick metal spinning sound like what I would imagine a dry bearing might make. The noise occurs, so far, only during warm start up after it has sat for 15 minutes to an hour. The noise only lasts for a second and then goes away. The mechanical oil gauge reads 50-55 psi at hot idle (around 800 rpms); 65-70 at cold idle. I've religously changed the oil at least every 1500-2000 miles with Mobil 10W30 and Motorcraft filter. This is my wifes truck and says she never hears it; I've heard it several times over the past month.
I have heard of oil draining back in oil filters-what about the Motorcrafts? Oil pump? Take the motor back to the rebuilder?
The thought of having to pull this engine for 3rd time in 2 years depresses me.
Thanks for the info.
I have heard of oil draining back in oil filters-what about the Motorcrafts? Oil pump? Take the motor back to the rebuilder?
The thought of having to pull this engine for 3rd time in 2 years depresses me.
Thanks for the info.
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Noise on start up...
Check out the starter bendix and the bearing that supports the end of the starter shaft. This may be the source of the noise as they tend to get dry after a while and heat does affect the performance of the starter due to its proximity to the exhaust pipes and manifold. Better to check it now before it calves on you and leaves you stranded.
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Joined: Jan 2001
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From: Rural Florida Panhandle
Noise on start up...
I agree about the starter. And if that is the problem, you could destroy the ring gear with it.
But if the starter is not the problem, I would try:
-Watch the oil pressure guage while cranking to see if the noise occurs before the pressure comes up. If you have oil pressure during the noise, it probably indicates your engine internals are good.
-Check other devices, such as power steering pump, compressor clutch, alternator, etc.
-Check for a loose or misaligned belt.
Winford
But if the starter is not the problem, I would try:
-Watch the oil pressure guage while cranking to see if the noise occurs before the pressure comes up. If you have oil pressure during the noise, it probably indicates your engine internals are good.
-Check other devices, such as power steering pump, compressor clutch, alternator, etc.
-Check for a loose or misaligned belt.
Winford
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Noise on start up...
It never would have occurred to me that the noise could be a starter going out. But come to think of it, one of the bolt tabs (where the starter bolts to housing) is broken off so maybe the starter is misaligned?
Thanks again for the input.
John
Thanks again for the input.
John
