how to check compression on glow plug ports
- Thread starter gssz
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I checked all three (of course they have a common positive rail), and they are measuring 10.95 V after about 4 to 5 seconds (they start a bit lower but get up to almost 11V). The shop manual says we should expect "approx battery voltage" so I suspect 11V is close enough. On the old glow plugs they stamped 11V.
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I unhooked the positive lead and it now measures exactly the same as the battery voltage (11.7V)
It’s not a glow plug problem. The OP said he ran it 30 min and it still starts slow.
It should start almost immediately. My BX1860 starts instantly more or less, even on cold days. I only use 3 sec of glow plugs, most of the time, even on cooler days. On colder days, like 25 degrees, I glow plug maybe 5 sec. After initial start I never use glow plugs, even if not fully warned up. After running about a min, it will instantly start with no glow plugs.
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It should start almost immediately. My BX1860 starts instantly more or less, even on cold days. I only use 3 sec of glow plugs, most of the time, even on cooler days. On colder days, like 25 degrees, I glow plug maybe 5 sec. After initial start I never use glow plugs, even if not fully warned up. After running about a min, it will instantly start with no glow plugs.
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Your battery should be reading over 11.7 volts if it is at 100% state of charge. Have you had your battery checked? Slower cranking speed can make starting more difficult.
Beex, Yes he did say that he ran it for 30 minutes and it was still hard to start. What he didn't say was how long after running was the start attempt made. It could have been within 2 minutes of shutdown or 120 minutes. Since it wasn't explicitly spelled out, it was worth asking. Agree it should start almost immediately.
I tried almost immediately after shutting it off (after running for 30 minutes). Per whitetiger's suggestion I paid more attention to the solenoid and I think I finally established that is the problem. After cleaning up and spraying some light grease in the solenoid, it is opening and shutting nicely.
Today for the first time it started several times within a couple of seconds! As I was observing the behavior of the solenoid, I found that if I move the key to start start position and then off, the next time I move it to the start (cranking) position, it shuts the solenoid and after about 5 seconds of holding the glow plugs, it starts right up )as in 1 to 2 seconds) IF the solenoid goes back to the ON (open) position immediately when I move the key to Start. However, it can randomly decide to wait 7 to 8 seconds to release the solenoid, which coincides with the 7-8 second delay I have been getting until now.
So it seems that the longer crank times occur when the solenoid it not opening to let the fuel through.
I guess this is either the solenoid itself not going back to the other position, or the key switch not telling it to go back to the open position. Is there any other intelligent system telling the solenoid to open or close?
Today for the first time it started several times within a couple of seconds! As I was observing the behavior of the solenoid, I found that if I move the key to start start position and then off, the next time I move it to the start (cranking) position, it shuts the solenoid and after about 5 seconds of holding the glow plugs, it starts right up )as in 1 to 2 seconds) IF the solenoid goes back to the ON (open) position immediately when I move the key to Start. However, it can randomly decide to wait 7 to 8 seconds to release the solenoid, which coincides with the 7-8 second delay I have been getting until now.
So it seems that the longer crank times occur when the solenoid it not opening to let the fuel through.
I guess this is either the solenoid itself not going back to the other position, or the key switch not telling it to go back to the open position. Is there any other intelligent system telling the solenoid to open or close?
True, he didn’t spelled out, but, my experience is once it’s up to full temp, mine is good for about an hour for a fast start with no glow plugs.
He has good compression, so I’m stumped on this, and am curious as to the resolution. So will be watching the thread.
Normally, with good compression and a hot engine, the only thing left is the injection pump, or fuel delivery to the injection pump. But both of those things would result in bad performance when running, and the OP said it runs fine once started. This is very weird.
Could it be a week electric pump so takes a while it to get enough fuel to start, but once it starts the injection pump can suck enough fuel through the line to run?
I have never heard of BX governor problem, but wondering if there is some malfunction that it can cause a slow start then work ok at normal speed? I don’t know how that could happen, but again this is a weird symptom.
Both of those seem dumb, but haven’t come up with a good idea yet.
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It looks like it's the stop solenoid 
per previous post, the longer cranking times coincide with the solenoid not going back to the ON position to let the fuel through. The moment that happens, the engine starts.
So it's either the solenoid not behaving properly, or the key switch is not telling the solenoid to open when it is in the Start position. I sprayed some silicone grease in the key switch as well in case the internal guts are not moving around easily.
Either way, we are down to two possibilities
per previous post, the longer cranking times coincide with the solenoid not going back to the ON position to let the fuel through. The moment that happens, the engine starts.So it's either the solenoid not behaving properly, or the key switch is not telling the solenoid to open when it is in the Start position. I sprayed some silicone grease in the key switch as well in case the internal guts are not moving around easily.
Either way, we are down to two possibilities
You beat me to the send but on your last post.
But I had thought your test of disconnecting the solenoid and still getting a slow start eliminated the solenoid. I must have misunderstood.
The way the solenoid works on mine, and probably supposed to work on yours is that it’s default position is always on, open, let the tractor start and run. When I turn the key from off to on, glow plug, or crank, the solenoid does nothing. The from the on position to the off position the solenoid triggers and pulls lever to shut off the fuel, engine shuts down. Then, while the key is still off, after a delay, the solenoid will release, and the fuel is open ready for a restart.
This design means if the solenoid fails, doesn’t work, the tractor will still start, run, but will require manual shutdown.
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So while cranking, the solenoid should be on (open) - correct? On mine, when it takes 8 seconds to start, the solenoid stays closed. As soon as it opens, the engine starts. If I had any prior experience, I would have known this But this is one way to get some experience! I love the learning so it is a fun chase. If it wasn't for this trouble, I would not have learned how to adjust the valve lash and test compression. Of course, if I was out on the field mowing all day and this happened, it would be less fun.
I really appreciate everyone's input!
But this is one way to get some experience! I love the learning so it is a fun chase. If it wasn't for this trouble, I would not have learned how to adjust the valve lash and test compression. Of course, if I was out on the field mowing all day and this happened, it would be less fun.I really appreciate everyone's input!
Just ran another test on mine, because I wasn’t sure what it would do. After turning key to off, and the solenoid tiggers and shuts the fuel off, if I turn the key back on before the timer releases the solenoid, the solenoid is released immediately turning the fuel on.
When I turn off, solenoid closes, and let the timer run out, it takes about 7-8 seconds, then the solenoid is releases and the fuel is back on.
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When I turn off, solenoid closes, and let the timer run out, it takes about 7-8 seconds, then the solenoid is releases and the fuel is back on.
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So while cranking, the solenoid should be on (open) - correct? On mine, when it takes 8 seconds to start, the solenoid stays closed. As soon as it opens, the engine starts. If I had any prior experience, I would have known this
I really appreciate everyone's input!
Yes, it should be open, anytime the key is on, glow plugging, or cranking. And it should be on MOST of the time when the key is off. The only time it’s supposed to be closed is for 8 seconds after you switch the key from on to off.
This is assuming the 30 series you have works the same as the 60 series I have. Which from the pics you posted of the solenoid , I don’t know why it wouldn’t. It looks the same as mine.
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The way your describing your solenoid behavior, it seems like it’s working backwards. Turn the key on, and there’s an 8 second timer delay before it turns on the fuel. Something is not wired correctly. The 8 sec timer is to make sure the engine is fully shut down after turning off the key, before releasing the solenoid turning the fuel back on.
No timer should be running when going from off to on.
Maybe in it’s past life someone replaced the key switch and messed it up.
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No timer should be running when going from off to on.
Maybe in it’s past life someone replaced the key switch and messed it up.
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it does open correctly about 7 seconds after I turn it off. I wonder if this relay is telling the solenoid when to open or close. It seems to be the only relay on the tractor. The picture is sideways but in reality the top position is really on top.
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Unplug the wire that goes to the shutdown solenoid and see if it starts immediately. If it does, re-connect the wire or use a long screw driver to push the shutoff lever to the no fuel position to shut it down.
The solenoid should only pull in after the key is turned off after being turned on. If it's pulling in when you turn the key on, the module may be bad or have dirty terminals.
I would pull the connector off the timer module in your picture, and check the terminals for corrosion.
My 2230 started not shutting down when I turned the key off, and I discovered there was no current going to the shutdown solenoid. I wiggled the connector on the timer module and it started working. I pulled it off and cleaned the terminals and it has worked fine ever since.
The solenoid should only pull in after the key is turned off after being turned on. If it's pulling in when you turn the key on, the module may be bad or have dirty terminals.
I would pull the connector off the timer module in your picture, and check the terminals for corrosion.
My 2230 started not shutting down when I turned the key off, and I discovered there was no current going to the shutdown solenoid. I wiggled the connector on the timer module and it started working. I pulled it off and cleaned the terminals and it has worked fine ever since.
I don't have the WSM for your machine, but here is what is posted for testing the timer relay. Perhaps it will give you some insight to aid in your diagnostics.
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Thanks. I am adding dielectric grease to any connections I pull - is that OK? I am guessing this is a universal good for electrical connections, but I am just guessing. In this case I will need to clean up the dielectric grease on the relay connectors as I squirted some in there without cleaning the terminals. They looked clean, but I will make sure to clean them as much as possible with a small file.
FYI, dielectric means it doesn't conduct electricity. Dielectric grease is designed to be used on electrical connections to prevent corrosion.