| [GMCnet] Engine troubles [message #273750] |
Sun, 15 March 2015 19:16  |
Advanced Concept Ener
Messages: 112
Registered: December 2014
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I suspect that the oil analysis is a spectrographic analysis. They burn off the sample and each type of metal gives off its own light bands. They will tell you what types and quantities of steel. Existence of bearing materials Babbitt , copper, etc. . If in high enough concentrations they can tell you if it is just starting or is about to be or has been a catastrophic failure.
There is a more expensive test called a ferrographic analysis. They actually look at the shapes of the particle and can tell what kind of failure you are experiencing. Together the the tests, if evaluated by an expert, pretty much what has happened and what to expect going forward. I don't know what this costs anymore because it has been 25 years since I got involved with this type of non-destructive testing done for the Navy.
Not sure if they figured how to do it cheaper by using computers.
If you get bad readings you may want to call them and ask if they also do other tests to get more information on your problem. If you have high copper contents however I would guess that means a wiped bearing and it time for rebuild or replacement. I may be looking at an engine problem as I have low oil pressure. I have ordered a sample bottle and will send it out within a month subject to digging out the coach. I will let you know what I found out.
Jon Darcy ACES
North Jersey 76 stretch, flares, 4 bag, Alcoa's, bunkhouse,MAC Dash
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| Re: [GMCnet] Engine troubles [message #274227 is a reply to message #273750] |
Mon, 23 March 2015 13:03  |
tgeiger
Messages: 518
Registered: February 2006
Location: kansas city
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Thanks Jon on this information. I've just collected the oil sample this past weekend and am sending off the sample to the lab today. Keeping my fingers crossed that it might be something loose attached around the engine. I'll keep you posted on what the results are. This all seem to happen, low oil pressure, noise, after my mechanic installed the cross-over blocking plates. I wonder if either one or more oil ports got blocked, or if the coolant port started leaking into the oil? I guess we'll see from the results of the test maybe.
Tom Geiger
76 Eleganza II
KCMO
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| Re: [GMCnet] Engine troubles [message #274379 is a reply to message #274287] |
Thu, 26 March 2015 08:19 |
Jim at the Co-op
Messages: 291
Registered: May 2014
Location: Orlando Florida
Karma: 2
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You need to carefully vacuum out ant carbon deposits found under the
intake, we pour a quart of oil across the valley after the vacuum to try
and nothave any particles get into any passages.
Did you use a fiber gasket (not the turkey tray) in bedding back the
intake? You do not use the valley pan gasket when installing SS blockoff
plates, we use the Mr. Gasket 404 intake gasket set for the 455 motors.
If you have a low end noise and low oil pressure, testing the oil is kind
of a waste. The bottom of the motor is now hurt, if it makes a noise with
oil pressure lower than before -- hate to say it brother but chances are
the block will need to come out. Listn to the motor carefully, fire it up
now and check it out, it will not heal itself given time....
Good luck,
Jim Bounds
On Tue, Mar 24, 2015 at 5:37 PM, A. wrote:
> tgeiger wrote on Tue, 24 March 2015 14:35
>> ...I do have a video with audio that I took with the hatch open and
> engine making the noise when I rev it up. Just don't know how to upload it
> to
>> this site.
> This site is effectively text only. Even HTML gets stripped off, maybe to
> level it up for use with the mail list server that mirrors it. Photos get
> posted to the photo repository ( http://www.gmcmhphotos.com/photos/ )
> which can also be used to store some forms of multimedia, but I don't know
> about
> .mov files.
>
> To include something other than text in a post to this forum, place it on
> the photo site and then include the URL of the media in the forum post.
> Detailed directions for IMBEDDING PICTURES in a post are contained in the
> sticky which is the first thread in this forum.
> --
> '73 23' Sequoia For Sale
> '73 23' CanyonLands For Sale
> Upper Alabama
> Stupidity is ignorance that refuses to be cured.
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| Re: [GMCnet] Engine troubles [message #274484 is a reply to message #273750] |
Sat, 28 March 2015 04:41 |
tgeiger
Messages: 518
Registered: February 2006
Location: kansas city
Karma: -1
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Hey Jim, i talked to the mechanic that installed the cross over plates and he didn't remember specifically but said the same that the turkey tray would have been removed if was the tray had also a intake gasket, but I seem to remember having a tray that was not a intake gasket setup in there so I 'm asking him to verify with the guy that did the work if that tray was removed. He said that if it didn't involve the installation of the cross over, then it might not have been removed. Does this tray if in place impede oil flow?
Tom Geiger
76 Eleganza II
KCMO
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| Re: [GMCnet] Engine troubles [message #274725 is a reply to message #273750] |
Wed, 01 April 2015 12:39 |
tgeiger
Messages: 518
Registered: February 2006
Location: kansas city
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Well got good news from the oil lab report, everything looks very good to them. Called and talk to them as well and he said there didn't appear to be any indication of bearing or metals, water or fuel in the oil that would indicate trouble. So I guess I need to take closer look at other items.
Tom Geiger
76 Eleganza II
KCMO
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| Re: [GMCnet] Engine troubles [message #274759 is a reply to message #273750] |
Wed, 01 April 2015 20:41 |
Steve
Messages: 506
Registered: September 2013
Location: East Greenville, Pa
Karma: 1
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That's good news. Glad to hear it.
1978 GMC Royal
Eastern Pennslyvania
1968 Chevrolet C20 396 Camper Special
1969 Chevrolet C20 Camper Special
1985 Buick Electra Park Avenue
1992 Camaro 25th Anniversary Heretage Edition Black
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| Re: [GMCnet] Engine troubles [message #274802 is a reply to message #273750] |
Thu, 02 April 2015 12:25 |
rvanwin
Messages: 325
Registered: April 2007
Location: Battlefield, MO
Karma: 6
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Might check the harmonic balancer. Mine had come de-laminated and would make noise at idle and slow idle but would go quiet at higher RPMs. At idle, it sounded a little like a rod knocking. This thread got broken so I couldn't easily find your original symptoms. I didn't find the problem until I was trying to set the initial static timing. Could never get the timing mark to stay put. Reached up and shook hands with the balancer and it was loose. Had a heck of a time getting the crank nut loose. We put the socket wrench on and anchored the handle against the frame and, after verifying the engine rotation directions multiple times, touched the starter. Popped the nut right off.
Randy & Margie
'77 Eleganza II '403'
Battlefield, MO
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