First stop on the diagnosis train: asking the forum., 1911 sounds like marbles in a tin can. |
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First stop on the diagnosis train: asking the forum., 1911 sounds like marbles in a tin can. |
Optimusglen |
May 15 2019, 11:56 PM
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#1
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Senior Member Group: Members Posts: 901 Joined: 26-February 16 From: Minneapolis Member No.: 19,709 Region Association: Upper MidWest |
A recent occurrence, I'm getting a pretty loud rattle that sounds like marbles swirling around the bottom of a tin can. Everything else seems fine, power etc. Hear it while in neutral and idling and also while driving in gear. It's drown out by wind noise the faster you go.
Engine is a 1.7 punched up to 1911 on dual Weber 40's. Heat exchangers stripped to bare headers, new muffler. Oil pressure and cylinder head temp both normal. |
falcor75 |
May 16 2019, 12:30 AM
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#2
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Senior Member Group: Members Posts: 1,579 Joined: 22-November 12 From: Sweden Member No.: 15,176 Region Association: Scandinavia |
Throwout bearing? Does it go away when you depress the clutch?
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jasons |
May 16 2019, 06:09 AM
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#3
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Jackstand Extraordinaire Group: Members Posts: 2,002 Joined: 19-August 04 From: Scottsdale, AZ Member No.: 2,573 Region Association: None |
Did something like a loose nut find it's way into your cooling fan?
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ejm |
May 16 2019, 07:40 AM
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#4
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I can see the light at the end of the tunnel Group: Members Posts: 2,688 Joined: 3-February 03 From: Massachusetts Member No.: 224 Region Association: None |
Could be the alternator bearings. Pull the belt and see if the noise goes away.
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rhodyguy |
May 16 2019, 08:08 AM
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#5
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,054 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
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Optimusglen |
May 16 2019, 08:59 AM
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#6
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Senior Member Group: Members Posts: 901 Joined: 26-February 16 From: Minneapolis Member No.: 19,709 Region Association: Upper MidWest |
I'm leaning alternator bearings... I took this video and uploaded it to Youtube, the noice is certainly coming from that area.
Throw out bearing seems ok, no change when clutch is depressed or released. Also took a look in the fan and all seems well, pulled out a small leaf but that was it. http://www.youtube.com/watch?v=wvZVJYsfrCU |
injunmort |
May 16 2019, 11:02 AM
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#7
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Senior Member Group: Members Posts: 1,024 Joined: 12-April 10 From: sugarloaf ny Member No.: 11,604 Region Association: North East States |
sounds like fan came loose from hub. try tightening three bolts on the hub.
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VaccaRabite |
May 16 2019, 11:10 AM
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#8
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En Garde! Group: Admin Posts: 13,417 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
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Optimusglen |
May 16 2019, 11:32 AM
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#9
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Senior Member Group: Members Posts: 901 Joined: 26-February 16 From: Minneapolis Member No.: 19,709 Region Association: Upper MidWest |
Fan is solid on the hub, that was the first think I checked, doesn't move at all except of course rotating.
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tejon007 |
May 16 2019, 01:56 PM
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#10
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Newbie Group: Members Posts: 45 Joined: 10-February 10 From: Northern California Member No.: 11,344 Region Association: None |
Sounds like the alternator needs some attention...maybe even the alternator mount is loose or broken.
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Dave_Darling |
May 16 2019, 04:57 PM
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#11
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914 Idiot Group: Members Posts: 14,980 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Pull the alternator belt and see if the noise stops. If so, the alt is your number one suspect.
--DD |
michael7810 |
May 16 2019, 04:57 PM
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#12
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Senior Member Group: Members Posts: 1,078 Joined: 6-June 11 From: Scottsdale, AZ Member No.: 13,164 Region Association: Southwest Region |
Almost sounds like a bad exhaust leak...but my hearing ain’t so good
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Optimusglen |
May 17 2019, 07:56 AM
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#13
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Senior Member Group: Members Posts: 901 Joined: 26-February 16 From: Minneapolis Member No.: 19,709 Region Association: Upper MidWest |
Parked it until I can dive into it more. The pulley on the alternator had some slop even though the bolt was tight, so that will be the next thing I look into and pull the belt and see how it sounds. I'll also check the exhaust since I did recently install a new aftermarket muffler and since you mentioned exhaust leak, no harm in checking it out.
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Optimusglen |
May 25 2019, 09:50 PM
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#14
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Senior Member Group: Members Posts: 901 Joined: 26-February 16 From: Minneapolis Member No.: 19,709 Region Association: Upper MidWest |
Fun stuff. And not fun stuff.
Ordered a new alternator, just the regular 55w one. Spent the afternoon swapping it in. In the process of pulling the old one out an ACORN fell out of it. Screwy. But, the pulley was loose even though the bolt was tightened down, the key was a bit mangled and the slot in the old alternator shaft was even more mangled so it was good I had a new one. Got everything buttoned up, went to connect the battery and suddenly there's billowing smoke. :[ Pull the battery cable and push it out into the driveway. Later climbed under and the alt harness is melty goo. Guessing a short to the alt back plate? New harness from 914Rubber on order. Anyone know if that type of thing would fry other components? Oh, and I installed a new alt cooling snorkle. The spring clip unsprung into the fan housing. Anyone with a good method of removing it? |
mcswiggs |
May 26 2019, 01:10 AM
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#15
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Newbie Group: Members Posts: 22 Joined: 31-January 18 From: London, UK Member No.: 21,845 Region Association: England |
Take the back plate off and check the length of the terminal studs and how close they are to that back plate when assembled. I know this is a problem on new alternators sold in the UK to bus owners. Good luck. Fun stuff. And not fun stuff. Ordered a new alternator, just the regular 55w one. Spent the afternoon swapping it in. In the process of pulling the old one out an ACORN fell out of it. Screwy. But, the pulley was loose even though the bolt was tightened down, the key was a bit mangled and the slot in the old alternator shaft was even more mangled so it was good I had a new one. Got everything buttoned up, went to connect the battery and suddenly there's billowing smoke. :[ Pull the battery cable and push it out into the driveway. Later climbed under and the alt harness is melty goo. Guessing a short to the alt back plate? New harness from 914Rubber on order. Anyone know if that type of thing would fry other components? Oh, and I installed a new alt cooling snorkle. The spring clip unsprung into the fan housing. Anyone with a good method of removing it? (IMG:style_emoticons/default/dry.gif) |
Mark Henry |
May 26 2019, 05:31 PM
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#16
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Did you put 911 valve adjusters on it? Some are real long and will hit the valve covers.
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Optimusglen |
May 28 2019, 08:18 AM
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#17
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Senior Member Group: Members Posts: 901 Joined: 26-February 16 From: Minneapolis Member No.: 19,709 Region Association: Upper MidWest |
No 911 valve adjusters.
Back onto the alternator discussion. I may have hooked the alternator condenser up to the wrong post when replacing it this past weekend. (IMG:style_emoticons/default/chair.gif) I have yet to pull it out, but thinking back it is possible. The new alt had longer posts and I knew enough to cut those down. The alternator wiring harness was old and not in the best shape but looked to be solid and in one piece, and since it was working well before I didn't swap it out. I suppose another possibility is that the harness cracked and created a short while I was moving it around during removal/installation. Either way, from my initial review it looks like there was a short and it melted the harness. I already ordered a new harness from 914 Rubber. From my research it is likely the alternator is toast too. I'm hoping those and some self respect, if I did miswire it, are the only casualties here. |
Optimusglen |
May 30 2019, 03:57 PM
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#18
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Senior Member Group: Members Posts: 901 Joined: 26-February 16 From: Minneapolis Member No.: 19,709 Region Association: Upper MidWest |
Update, swapped on alternator #3 on with a new harness from 914Rubber. Works like a charm and runs quiet. So the rattle was definitely from alternator #1. Probably a combination of the acorn inside and the sloppy pulley.
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