Any ideas? Our starter is going bad. It is a 24 V, for a MCI DL3. Should we just order it (from where), or have it rebuilt? Usually it starts on maybe the third try, but today it wouldn't after many tries. I got the rubber mallet out and started swinging at the starter. It started on the first try, for sheer fear that I would keep beating on it ;D ;D ;D.
Thanks in advance,
God bless,
John
I can say without a shred of a doubt that this is what you need:
http://www.delcoremy.com/Starters39MT.aspx (http://www.delcoremy.com/Starters39MT.aspx)
Review this thread for the history of my starters which culminated in an MT39 (and which is still working, thank you very much Tom for that recommendation.):
http://www.busconversions.com/bbs/index.php?topic=1427.15 (http://www.busconversions.com/bbs/index.php?topic=1427.15)
John; take it off and have it rebuilt will be cheaper than a exchange but first check all the cables and the voltage on the batteries Hope you are strong or have a good floor jack (do you have 60s DD) have a great day
MMA2S, Yes it is a DDEC S60. Other than the starter (now that I think about it, we have a fuel temp sensor that is bad) we haven't had any problems with that setup. Especially the S60 is an awesome engine.
Thanks and God bless,
John
John; have your Delco 42 rebuilt better starter for a 60 series than a 39MT have a great day and yes the 60s are a great engine plenty of power with fuel economy
This is in the category of "Bob learning more" rather than "Bob arguing" - why would you say the 42 series is a better starter for the S60? My understanding is that the MT39 series is a higher torque starter than the older 42 series. It also has the advantage of being substantially lighter. FWIW it was a 42 series that I replaced, 3 times in quick succession.
John, while it is tempting to replace the starter, it is in your best interests to properly diagnose the problem. When removing or replaceing starter it is possible to mask another problem. Better to know for sure what problem is befor taking things apart or spending money needlesly!!
I am looking for the thread that Sojourner posted some time back. He explained in detail how to do the diagnostics. Jim
Before the tests, the batteries should be at 80% or higher state of charge for diagnostic checks but not cranking voltage test unless full state of charge.
I attached a wiring circuit with numbers which label each test points.
A) NC fuel pressure switch:
1) Hook + test lead to #7 and – test lead to #8...while cranking, it should read 0 voltage until it starts.. If it erratically or full battery voltage before engine run...bad pressure switch. Hook up + test lead to #8 and – test lead to chassis GRD... it should read 0 voltage until it starts. If it erratically or full battery voltage before engine run...poor ground wire or connection.
2) If fuel pressure is higher then 8 psi @ cranking speed...checks for restricted return fuel line flow. It will cause the starter to shut down automatically.
B) Starter switch relay before solenoid:
1) Hook up analog meter + test lead to #6 and – test lead to chassis ground...it should be at battery voltage while cranking. Otherwise if it erratically meter movement....bad starter button switch or wire connection.
2) Hookup analog meter to solenoid coil post (#5) (it the same + from battery post) with + lead and – lead to (#4) pressure switch. Watch voltage meter for steady cranking voltage reading while hold down the start switch...if it 0 voltage while cranking is good. If it does erratically while using either front or rear starter switch mean bad wire connection to or in the relay or bad relay points.
C) Solenoid:
Hookup analog volt meter with + test lead to + post (#1) of solenoid and – test lead to starter's + post (#2). Watch for meter goes to 0 voltage while cranking...that is good. But if it erratically...bad connection either in solenoid's contact switch or starter's brushes or wire connection. Take it to repair shop for further testing or replace both solenoid & starter motor with warranties.
D) Bendix Drive:
1) Wrinnninnnn noise (spinning) mean over run clutch is slipping, mean a bad bendix drive.
2) Very loud gear clashing before fully engage...either worn gear's teeth or starter is spinning before fully engage...solenoid connecting link is out of adjustment or worn out. Replace both solenoid & starter motor with warranties.
E) Starter Motor:
Hookup analog or digital volt meter to solenoid's + post (#1) and the – lead to engine's ground. Watch for voltage dropping at the beginning & during cranking. If the voltage is below 18v with a fully charged 24v system and growling noise mean starter bearing is worn out to cause armature to rub on field poles. Replace both solenoid & starter motor with warranties. If no growling noise...check power source for weak & "hot" (high resistance) connection of both the + positive & - negative. While cranking with fuel shut off, it should never have more then .5 volt drop between #1 and starting battery's + post. Same way with grounding between engine to battery – post of no more then .5 drop.
I cannot find original post, Wiki will be great when it is done!!! I am unable to post drawing the Jerry provided.
HTH Jim
JJR...thanks
I post a picture for JJR post.
About 39MT starter....it the state of art design version. High RPM motor via gear reduction to reduce the needed of the higher ampere current as the older version. However, I do not know its mechanical reliability of it. Other who has them can tell you that part. I am interesting to learn the new history.
FWIW
Sojourn for Christ, Gerald
About 24v or 12v. Always go for the highest voltage system for better power source to any appliances with same OEM size wire.
FWIW
Sojourn for Christ, Gerald
Jerry and Bob DD has had a lot of problems with that starter, the drive system,the solid link solenoid, brushes, and leaks it is a cheap starter compaired to MT42 costing around 800 + bucks new.It is not OEM on DD 60s anymore because of the problems.On a 2 stroke it should be fine they don,t have that much compression to start with, but they don't last long on a 60s even with the Delco folks telling you it is good up to 15L engines. have a great evening
My sample size of one doesn't match that experience but that's good to know anyway. I put 3 of the MT42's (2 from NAPA & 1 from Prevost) on in under 2 years. I was at my wits end when I started the thread that I referenced earlier. Tom recommended the MT39 and it has performed flawlessly ever since. We had a small issue getting the right head on it at the outset but since then it has never missed. With the 42s I had got to the point where I was paranoid about not over cranking. I still don't abuse the starter but I am finally getting over some of that paranoia and don't stroke out if the engine doesn't light up on the first turn.
As far as pricing was concerned there was certainly no significant difference at the level I was buying them at. As I recall the 39 was actually a little higher priced but that could be oldtimers kicking in.
Hey guys, thanks for the input.
jjrbus, I will start going through the troubleshooting that you suggested. I am pretty confident that it is the starter. The starter is the one thing that we haven't replaced preventively. Our new batteries are in great condition. Wouldn't it sure seem like the starter when it will crank, while you are knocking it on the side with a rubber mallet? That is how I got ours to start (beat on the starter while someone else starts it).
Thanks for all the starter advice. It gave me a good foundation for getting the right starter.
God bless,
John
I would also @$# u me it is the starter. But at a min of $250 for a rebuild I would want to be as close to 100% as I could get. This is also a great time to learn about the system, where things are and how they interact.
Credit should go to Jerry Jenkinson for the time and effort he put into sharing his years of experience and making it available. Jim