72 1.7 Burning oil, After brief warmup blue cloud |
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72 1.7 Burning oil, After brief warmup blue cloud |
MNnewbie |
Apr 13 2017, 04:05 PM
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#1
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Newbie Group: Members Posts: 11 Joined: 10-June 14 From: MN WBL Member No.: 17,466 Region Association: Upper MidWest |
Looking for any advice I can get regarding a 1972 1.7 w 48k on the motor
It starts fine when its cold but once it has ran for 5-7 minutes and driven it starts blowing a lot of blue smoke. So much so that there are drop of oil coming off of the tailpipe. Have not checked compression yet -hope to tonight |
injunmort |
Apr 13 2017, 04:09 PM
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#2
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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 |
need more. has it been sitting? comp check first, could be rings, valves etc, need more info
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Rand |
Apr 13 2017, 04:19 PM
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#3
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
Sorry for the dumb question, but asking to learn: How could blue oil smoke be valves? Wouldn't it have to be rings (or scarred cylinders)?
Compression and leak down test will surely reveal some answers, no question there. |
mgphoto |
Apr 13 2017, 05:45 PM
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#4
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"If there is a mistake it will find me" Group: Members Posts: 1,338 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California |
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Rand |
Apr 13 2017, 05:54 PM
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#5
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
Sorry for the dumb question, but asking to learn: How could blue oil smoke be valves? Wouldn't it have to be rings (or scarred cylinders)? Compression and leak down test will surely reveal some answers, no question there. worn valve guides. Oof, of course. Thanks. Back in the day when I was raising a family, we had a Dodge Caravan. It was of that era where they had valve guide problems. It would run clean, until you let it idle. Which was a nightmare at stoplights... It poofed a batman style smoke screen on takeoff. (IMG:style_emoticons/default/biggrin.gif) |
MNnewbie |
Apr 14 2017, 09:27 AM
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#6
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Newbie Group: Members Posts: 11 Joined: 10-June 14 From: MN WBL Member No.: 17,466 Region Association: Upper MidWest |
The car had been driven last summer off and on for 4 months.
The last day I drove it last fall it had been running fine when suddenly the blue cloud appeared and I lost power. I figured that it was one of the problems that has been mentioned but when I restarted it this spring it ran- idling and revving the motor were ok, until I started to drive it. Will do the various compression/ leak tests down this weekend and post results. |
mgphoto |
Apr 14 2017, 12:51 PM
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#7
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"If there is a mistake it will find me" Group: Members Posts: 1,338 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California |
Pull the spark plugs, check the condition, if oily black get a set of hotter plugs for the time being, she will burn the oil off.
Mike |
IronHillRestorations |
Apr 14 2017, 02:57 PM
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#8
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I. I. R. C. Group: Members Posts: 6,716 Joined: 18-March 03 From: West TN Member No.: 439 Region Association: None |
Sounds like a broken ring to me, but anything is a guess.
I'd do a compression, leakdown, and vacuum test. One of those will point you toward the problem. |
injunmort |
Apr 14 2017, 03:36 PM
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#9
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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 |
worn guides or mushroomed valves will allow oil into the combustion chamber, blue smoke to ensue
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MNnewbie |
Apr 24 2017, 09:28 AM
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#10
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Newbie Group: Members Posts: 11 Joined: 10-June 14 From: MN WBL Member No.: 17,466 Region Association: Upper MidWest |
I finally got around to doing a compression check
120 120 120 90 Put a couple of squirts of in the 90 cylinder and got 95. Which leads me to think its probably in the valve train. Knowing what I am looking for and where to start should make it easier. Appreciate the comments so far. |
Ansbacher |
Apr 24 2017, 09:36 AM
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#11
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Senior Member Group: Members Posts: 689 Joined: 4-July 14 From: Tampa Bay, Florida Member No.: 17,589 |
I had the same symptoms with my first 914 back in the eighties. Started good, ran good till hot, then smoked like a B-52 on takeoff. Turned out to be valve guide tube seals, as others have said here. Good luck.
Ansbacher |
TheCabinetmaker |
Apr 24 2017, 10:41 AM
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#12
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Valve guide tube seals? (IMG:style_emoticons/default/confused24.gif)
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MNnewbie |
Apr 24 2017, 10:51 AM
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#13
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Newbie Group: Members Posts: 11 Joined: 10-June 14 From: MN WBL Member No.: 17,466 Region Association: Upper MidWest |
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Dave_Darling |
Apr 24 2017, 01:16 PM
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#14
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914 Idiot Group: Members Posts: 14,981 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Turned out to be valve guide tube seals... No such animal. There are pushrod tube seals, which leak oil down onto the heat exchangers and cause smoke to come up from under the car. There are valve guides, which will generally cause smoke to come out of the tailpipe on overrun (throttle closed, coasting down from high RPM in gear). Other cars may have valve stem seals, whose failures would tend to lead to similar symptoms as this, but our 914s don't have them. Smoke from under the car means an oil leak out onto the exhaust. Smoke from the tailpipe means a problem inside the engine. --DD |
injunmort |
Apr 24 2017, 06:42 PM
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#15
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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 |
there are no guide seals on a type IV. 90 is low and and adding 90wt brings up compression, i am leaning toward a ring issue not guide/valve. dosent matter though, to address either requires pulling engine and top end disassembly. to inspect and measure rings and piston/wall clearance. if the engine is not making any strange noise, probably rings, if it "ringing like a bell" maybe bore and piston.
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MNnewbie |
May 4 2017, 02:46 PM
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#16
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Newbie Group: Members Posts: 11 Joined: 10-June 14 From: MN WBL Member No.: 17,466 Region Association: Upper MidWest |
there are no guide seals on a type IV. 90 is low and and adding 90wt brings up compression, i am leaning toward a ring issue not guide/valve. dosent matter though, to address either requires pulling engine and top end disassembly. to inspect and measure rings and piston/wall clearance. if the engine is not making any strange noise, probably rings, if it "ringing like a bell" maybe bore and piston. I stalled out last weekend on removing the engine and tranny but have my confidence back and plan on doing so this weekend. Any recommendations for a mechanic or machine shop in the St Paul Mpls area also appreciated. |
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