Rough Starting What to Check

Topic: Rough Starting What to Check (Read 1091 times) previous topic - next topic

Rough Starting What to Check

June 24, 2018, 02:12:12 pm

We left for a Rally on Tuesday and when we went to start the starter was sluggishly spinning the engine. We had 13.4v on the house batteries and 13.3v on the chassis and we were using the boost switch. After starting I turned it off and it started fine. Leaving the rally today it did the same thing. Chassis batteries are new with the Trik-L-Start on them. Where should we start looking? Thinking of checking all of my connections starting at the batteries to the starter, to solenoids and the battery isolator. Could the brushes in my starter be going bad?

Re: Rough Starting What to Check

Reply #1 – June 24, 2018, 02:16:38 pm

May want to check your ground wires too. Clean connections and tight.

Re: Rough Starting What to Check

Reply #2 – June 24, 2018, 02:27:46 pm

Check all connections at batteries, starter and grounds.

Sounds like voltage drop between batteries and starter. This is assuming that battery voltage does not drop below about 12.0 VDC while cranking (if it drops more, batteries are either bad or not charged). So, easiest place to start (from a location standpoint) is to put a voltmeter on the chassis battery and have someone crank it.

Re: Rough Starting What to Check

Reply #3 – June 24, 2018, 02:43:01 pm

I'm not sure why you have to use the boost switch. I've never used it, even in temps in the low twenties. I agree with the above posts, though your batteries register the same as mine, which is full charge with only usual coach draw on them.

Re: Rough Starting What to Check

Reply #4 – June 24, 2018, 02:52:02 pm

The connectors where the battery meets the starter on the frame were not making a good connection on mine and I had to buy a set of the connectors as the stud was turning in the connector when I tried to take it off to clean.

Re: Rough Starting What to Check

Reply #5 – June 24, 2018, 05:10:10 pm

Clean both battery posts as well as the inside of the terminals. File the cable ends flat to get maximum contact area too. If this hard starting is new, it's probably the connections. Like other have said, check grounds battery to chassis and engine to chassis. You should never have to use the boost switch.

Brushes could be going bad but lower percentage than battery or ground connections.

Pierce

Re: Rough Starting What to Check

Reply #6 – June 25, 2018, 07:06:08 am

Went to move coach after unloading. When placing ignition key to the on position everything on dash was normal. I looked at digital volt meter on dash while starting and watched voltage drop down to about 9.3v, then jumped to 10.3v and finally to 12.3v when it started. Will look at all of my connections and solenoids tomorrow. I was reading previous post on start solenoids and found that on my coach I have 2 ignition solenoids/relays, 1 starter solenoid/relay and 1 boost solenoid/relay. Is this correct? Ignition solenoids/relays are located at the foot of the passenger seat behind the panel. The start and boost solenoids are located under the bed on the wall by the isolator. Which solenoid is the boost and which is the start solenoid? Are they the same part number?
Thanks, John M.

Re: Rough Starting What to Check

Reply #7 – June 25, 2018, 09:34:56 am

The boost solenoid should be by the chassis battery and the start solenoid on the inside wall of the bed/engine wall. The start solenoid powers a large solenoid on the starter itself. The problem is most likely in the circuit from the batteries to the solenoid on the starter as this provides the current to run the starter and the other circuit only powers the engagement of the solenoid on the starter. Clean grounds to the starter are just as important to make a complete circuit for the starter motor. Good luck!

Re: Rough Starting What to Check

Reply #8 – June 25, 2018, 10:30:06 am

John, the boost solenoid on our coaches is under the bed against the wall by the isolator, One leg of the isolator goes on each side of the boost solenoid. You are correct the ignition has 2 relays behind the panel in front of the passenger seat. If we have a starter solenoid besides the one on the starter it must not be one similar to the boost one as I have never seen it.

Re: Rough Starting What to Check

Reply #9 – June 25, 2018, 11:20:19 am

Quote

Which solenoid is the boost and which is the start solenoid?

Here's a photo showing the layout on the isolator panel for the starter solenoid and the boost solenoids. This is from a 97 270 but I think it's about the same on a 99 320.
jor

Re: Rough Starting What to Check

Reply #10 – June 25, 2018, 04:57:21 pm

Well, after returning home from my VA appointment today I went to check the solenoid arrangement under the bed. I only seen one solenoid on the wall by the isolator. My guess it is the boost solenoid. So is the the start solenoid on the starter itself. Am I correct that my coach does not have a separate start solenoid like in Jor's photo. My next step is to check and clean all of my connections from the batteries to the starter. If the solenoid on the starter is bad, does the whole starter get replaced?
Thanks, John M.

Re: Rough Starting What to Check

Reply #11 – June 25, 2018, 05:18:01 pm

John, does the starter, when key activated, make ANY noise or a 'click click' sound, or a 'groaning' sound?

Re: Rough Starting What to Check

Reply #12 – June 25, 2018, 05:30:55 pm

Quote from: John Morales – June 25, 2018, 04:57:21 pm

Well, after returning home from my VA appointment today I went to check the solenoid arrangement under the bed. I only seen one solenoid on the wall by the isolator. My guess it is the boost solenoid. So is the the start solenoid on the starter itself. Am I correct that my coach does not have a separate start solenoid like in Jor's photo. My next step is to check and clean all of my connections from the batteries to the starter. If the solenoid on the starter is bad, does the whole starter get replaced?
Thanks, John M.

You are correct that you don't have the start solenoid like Jor's under the bed. there are a couple of relays mounted there and I don't know what they do. The solenoid is replaceable without the starter. But usually a solenoid is go no go, not dragging like a starter motor. I had the same starter issues before getting all the connections good.

Re: Rough Starting What to Check

Reply #13 – June 25, 2018, 05:34:50 pm

Quote

I only seen one solenoid on the wall by the isolator.

John, here's a photo of the isolator board on my 270 before I cleaned it up and relocated it. The starter solenoid was hidden behind a gaggle of wiring. I had to cut it all away to see it. In the three we've had the starter solenoid has always been on that board. Can't see why anyone would relocate it.
jor

Re: Rough Starting What to Check

Reply #14 – June 25, 2018, 05:37:12 pm

Quote

there are a couple of relays mounted there and I don't know what they do.

I have the same two relays. They are for the A/C. Here's a photo of all the parts on my isolator board.
jor

Re: Rough Starting What to Check

Reply #15 – June 25, 2018, 06:09:25 pm

Quote from: mike leary – June 25, 2018, 05:18:01 pm

John, does the starter, when key activated, make ANY noise or a 'click click' sound, or a 'groaning' sound?

Mike,
From the pilot seat it would be hard for me to hear any strange noises. When I turn the key the starter drags then all of the sudden spins. That is when I see the voltage fluctuation on the dash. I don't believe it's the start batteries because it does the same with the boost switch on. Will crawl under tomorrow and check starter connections, engine ground and all cable connections coming off of the batteries. Will also ask my wife to crank so I can listen to the starter close up. Attached are some pictures of my isolator area. Picture #1 has a few relays I don't know what they are for. Picture #2 has an unknown positive connection. Picture #3 is what I believe is my boost solenoid. I dug in the bundle of wires and could not see another solenoid.

Re: Rough Starting What to Check

Reply #16 – June 25, 2018, 06:48:27 pm

John based on the pictures you showed, I see lots of potential issues. I recently took apart all those connections and cleaned them with contact cleaner. Then I took emory cloth and a brass wire brush and cleaned every nut, stud and washer. I cleaned the battery terminal both house and engine. And I even cleaned the alternator connections. I made sure everything was on tight. I would have cleaned the starter connections but I was to tired and too fat to get to it. Since then my voltages are spot on and it fires instantly.

Re: Rough Starting What to Check

Reply #17 – June 25, 2018, 10:34:12 pm

Sounds like some connections to me as well. The other thing I thought of is how old are your start batteries? Could that be a issue as well ? Good luck with this John and let us know please what you find.
Bob

Re: Rough Starting What to Check

Reply #18 – June 25, 2018, 10:55:40 pm

John, you really need to clean all those terminals! That's the number one caus of hard starting,

Re: Rough Starting What to Check

Reply #19 – June 25, 2018, 11:07:32 pm

I would start with the ground wires as they are usually the most neglected. Just my 2 cents.

Re: Rough Starting What to Check

Reply #20 – June 27, 2018, 12:29:48 pm

Monday was tied up with the VA and errands and it rained all day yesterday. I went out to the coach today. I wanted to start the coach so I can raise it up and it started instantly within seconds on the first turn. No boost, no drag on the starter and no voltage fluctuation. I have done nothing but just parked it after I unloaded everything. I'm still going to go through all of the connections.
John M

Re: Rough Starting What to Check

Reply #21 – June 27, 2018, 01:11:41 pm

Ther starter and the weak grounds can be temperature sensitive. The starter itself is prone to not working if it over heats as it gets old.
Looking at the ground and general cable connections , I would fix all of them ffirst, and if it fails put a volt meter on the starter while cranking and see what gets delivered under load.

Re: Rough Starting What to Check

Reply #22 – July 03, 2018, 06:14:33 pm

John, The starter solenoid , on the starter it's self, can be rebuilt , the kits are available and not expensive. It's easer to remove the starter, check the bushings, bearings, and brushes while relacing the pate ,plunger and contacts ...

Dave

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