Yanmar problems
- Thread starter higgs
- Start date
check all your battery connections on both ends and also your battery to see if it is up to the proper power level... and if they are all good then you may have to rebleed your fuel lines ...and don't rule out the starter being your problem ..but do the free stuff first and go from their
My 2GM20F was always hard to start, unless it was warm, or was running the previous day. I decided to replace the mixing elbow this year, only because the PO said he never replaced it. Now... Perfect 1 click starting... Anytime.
20 years as a diesel mechanic I've alot of silly things happen. If if was hard to start after the filters were changed I would do 2 things, 1) pull filters and refill with fuel and while there off make sure the old seal didn't stick to the housing cause it happens.2) after filling filters pump your primer and see how if starts then, if there's still issues while it's running crack the injector line at the injector til fuel comes out, trapped air is tricky. Just as a side note I've also seen filter housings crack inside causing cavitation which produces air inside the system, hope it helps.
As you probably know a diesel engine burns the fuel mixture by the heat created by compressing it. Upon start up the engine will build adequate compression by repeated cranking strokes. Also adequate cranking speed is necessary to sustain the gradual buildup. If the engine turns too slow the heat build up will not be sufficient to ignite the fuel. A fully charged battery helps turn the starter motor and opening up the throttle helps supply a larger volume of the air/fuel mixture to be compressed. An obstruction in the intake or exhaust of the engine can restrict cranking speed.
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Ours (2gmf20) has always been a bit difficult to start the first time. After that, it starts instantly until I ignore it for a week or more. Our old SB12 (one cylinder) never faltered.
I've changed filters, bled, bled, bled. New batteries and rechecked connections (It seems to spin fast enough on the starter.)
I've checked valve clearance. On long trips (where it gets started daily) it always starts instantly (even when it's cold in the morning.) so I doubt it's air in the fuel line. Also when it doesn't start easily it only hits on one cylinder a few times. I'm suspecting an injector, or I may have lower compression in one cylinder. (I don't have a suitable compression tester.) When we got the boat it didn't have an hour meter so I have no idea the hours.
Ken
I've changed filters, bled, bled, bled. New batteries and rechecked connections (It seems to spin fast enough on the starter.)
I've checked valve clearance. On long trips (where it gets started daily) it always starts instantly (even when it's cold in the morning.) so I doubt it's air in the fuel line. Also when it doesn't start easily it only hits on one cylinder a few times. I'm suspecting an injector, or I may have lower compression in one cylinder. (I don't have a suitable compression tester.) When we got the boat it didn't have an hour meter so I have no idea the hours.
Ken
Ken, EXACT same symptoms I had (even the same engine). Problem: Blocked exhaust elbow. Not that hard to change. Took the old one to the good folks at Tacoma Diesel where they (using their vise) separated the exhaust flange and installed the new elbow at no charge. The only PITA was getting the exhaust hose off, which I can provide more detail if you need.
Because it seems to be winter around here (now that it's spring) and there is no glow plug? It was in the 30's when I woke up yesterday morning. We seem to be making up for the lack of winter. You had snow flurries on Sunday, no? A lot of Pennsylvania did.
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Thanks mz4wheeler
I first tried running a welding rod through but it couldn't make the bend. As much as I could manipulate it, no coke of any size came out. Because this boat is newish to us I don't know what the history is, but I can make a bit over 3.100 rpm. I would expect that to be a problem if it were plugged up, but then I don't know what RPM I should get with this particular prop.
Now that I think about it however I guess I could order one and then have a spare if it doesn't help.
And for you Scott T-bird It's been into the 80s this spring (but only 66 so far today.) We're at 48 degrees North. Odd weather indeed.
Ken
I've already removed the exhaust elbow and ran water from a garden hose through it with no restrictions.
I first tried running a welding rod through but it couldn't make the bend. As much as I could manipulate it, no coke of any size came out. Because this boat is newish to us I don't know what the history is, but I can make a bit over 3.100 rpm. I would expect that to be a problem if it were plugged up, but then I don't know what RPM I should get with this particular prop.
Now that I think about it however I guess I could order one and then have a spare if it doesn't help.
And for you Scott T-bird It's been into the 80s this spring (but only 66 so far today.) We're at 48 degrees North. Odd weather indeed.
Ken
Not sure about the water test... Mine looked OK to me, it wasn't completely blocked, otherwise the engine wouldn't run AT ALL. When I took it to Tacoma Diesel they right off the bat told me how bad it was, and showed me a new one to compare. Huge difference. I can get 3500 RPM in gear.
I was responding to Higgs Post #1. Although I can't figure out why he would have a 1GM on his boat. I assumed he was talking about another engine that he perhaps was not entirely familiar with. He said the engine runs great once started. I would guess that tosses out the mixing elbow theory. My 1GM was always hard to start in late fall when the weather dropped down overnight. Assuming the boat is on Lake Ontario, I would guess it is still like an ice box in the engine compartment. What's the water temp ... still in the 40's? We missed winter during the traditional months. It showed up in April and we haven't quite broken out if it yet, it seems. It looked like lake-affect snow was blowing across Lake Ontario over the past weekend. Without a glow plug, I think hard-starting in cold weather is a normal circumstance.
My engine ran great once it started too. It just became gradually more hard to start, and gradually the top-end RPMs were suffering.
To start a balky old diesel without glow plugs: 1) take a hair drier put it on high and let hot air flow into the yan air intake for 3 or 4 minutes, or 2) yan makes an electric 12v heat resistance grid that fits onto the air intake for some engine models -- turn it on and it warms the air. good luck.