Recent Topics
Burning off fuel dilution?
by Spetz. 10/23/18 07:19 PM
Clear Headlight Cover Correction?
by legandrex. 10/23/18 07:02 PM
FEDERATED PG 2500F CUT OPEN
by 53' Stude. 10/23/18 06:53 PM
Found a video on 6F35 disassembly
by SirTanon. 10/23/18 06:10 PM
Outboard oil safe to use in lawn mower?
by Jack2468. 10/23/18 05:43 PM
My Latest Purchase: 95 Chevrolet K1500
by dogememe. 10/23/18 05:05 PM
Ford factory filter vs MC FL500
by Arob. 10/23/18 03:15 PM
Fees for selling business products on Amazon?
by Ed_Flecko. 10/23/18 03:15 PM
Castrol Magnatec 5w20
by buster. 10/23/18 02:06 PM
Soft brake pedal culprits?
by nthach. 10/23/18 01:46 PM
WalMart Valvoline MaxLife 5W20 not SN+
by Silver. 10/23/18 01:32 PM
Pennzoil Availability....alte
rnatives?

by BTLew81. 10/23/18 01:16 PM
Revisiting Fumoto Washer - blue or OEM?
by buster. 10/23/18 12:02 PM
Detonation, Now only at high RPMs
by NICAT. 10/23/18 11:51 AM
List motor oils based viscosity index?
by Onetor. 10/23/18 10:37 AM
hard drive space keeps filling up on virtual machine
by oilpsi2high. 10/23/18 10:08 AM
Newest Members
WmMaroon, hogan646, hermie, avatar299, dexterbb
66281 Registered Users
Who's Online Now
125 registered members (Audios, alcyon, 1medic, 53' Stude, Astro_Guy, 12 invisible), 1,785 guests, and 37 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics292,432
Posts4,879,516
Members66,281
Most Online2,494
Oct 17th, 2018
Donate to BITOG
Previous Thread
Next Thread
Print Thread
Hop To
Page 1 of 2 1 2
Lawn tractor hard starting #4688668
03/08/18 12:59 PM
03/08/18 12:59 PM
Joined: Jul 2006
Posts: 2,143
Virginia
Tom NJ Offline OP
Tom NJ  Offline OP
Joined: Jul 2006
Posts: 2,143
Virginia
I have a Husqvarna 48" lawn tractor with a 24 HP Briggs & Stratton engine that has been used for three seasons cutting one acre of grass. I bought it new and up until last year it always started instantly, but during the last cutting season it became very hard to start.

I changed the oil, the oil filter, the air filter, the gas filter, and the blades, cleaned the spark plugs, sprayed solvent through the air intake, and ran a couple of tanks of gas with double-dose Techron, but to no avail (I always use non-ethnaol gas). I know the battery is weak as it dies after about 15 seconds of cranking, and I'll replace it soon, but even when I jump it with my car it still takes about 15-20 seconds to start in spite of the high cranking speed.

Now here's the kicker - when it does start it runs like a champ for the 1.5 hour grass cutting. I would think that some conditions that could cause the hard starting, such as a dirty carburetor, would also affect the running. I am wondering if a crack of pin hole in the gas lines is causing the gas to drain back to the tank, requiring more cranking to prime the lines (there is not obvious leaking to the ground or gas odor). That said I would also think that line priming would be rather fast.

Any ideas I should try next?

Tom

Re: Lawn tractor hard starting [Re: Tom NJ] #4688678
03/08/18 01:07 PM
03/08/18 01:07 PM
Joined: Sep 2015
Posts: 5,955
Kalifornia Kollective
BrocLuno Offline
BrocLuno  Offline
Joined: Sep 2015
Posts: 5,955
Kalifornia Kollective
It may not be choking correctly. It could be weak spark cranking.

Can you get to the carb easily? Spray just a shot of starting fluid and then crank. If it starts right up, you have a choking early fuel issue. If it's still lazy it's prolly the ignition ...

New battery and clean both ends of the ground cable. Use some silicone grease to make sure no rust under chassis end. Loosen and re-tighten at least one engine mounting bolt to get a good chassis ground. Loosen and re-tighten the bolts or screws that hold the ignition in place so that they have good return path for the spark energy.

What's the plug gap? Are you using fine wire or platinum plugs? OPE (Outdoor Power Equipment) has some of the wimpiest on the planet. They do not age well. They get internal corrosion, etc. But we put the cheapest plugs in them and expect them to work well. They are candidates for the easiest plugs to fire to help them along ...

I'd get an adjustable spark tester off eBay and see what kind of spark energy you are actually making? Then go from there smile

Last edited by BrocLuno; 03/08/18 01:14 PM.

Formerly in marine engineering. In an earlier life I owned my own petroleum tank truck, and hauled for the majors and independent's.
Re: Lawn tractor hard starting [Re: Tom NJ] #4688683
03/08/18 01:14 PM
03/08/18 01:14 PM
Joined: Sep 2011
Posts: 93
Ol' Kentuck
Squirrelee Offline
Squirrelee  Offline
Joined: Sep 2011
Posts: 93
Ol' Kentuck

Last edited by Squirrelee; 03/08/18 01:17 PM.

Some guy's dog thinks I'm a good man.
Re: Lawn tractor hard starting [Re: Squirrelee] #4688689
03/08/18 01:20 PM
03/08/18 01:20 PM
Joined: May 2015
Posts: 175
Virginia
GravelRoad Offline
GravelRoad  Offline
Joined: May 2015
Posts: 175
Virginia
Yes, check choke adjustment. We see this a lot on Husqvarnas with manual choke on B&S V-Twins. New and used.


2016 Subaru Outback Premium 2.5. PP 5w30 oem filter
2018 Hyundai Kona 1.6T. Lifetime dealer free oil/filter change
Re: Lawn tractor hard starting [Re: Tom NJ] #4688692
03/08/18 01:25 PM
03/08/18 01:25 PM
Joined: Sep 2015
Posts: 5,955
Kalifornia Kollective
BrocLuno Offline
BrocLuno  Offline
Joined: Sep 2015
Posts: 5,955
Kalifornia Kollective
Yeah, a valve adjustment may help too. Run them a wee bit on the loose side. More TQ and better valve cooling. It's not a NASCAR engine smile


Formerly in marine engineering. In an earlier life I owned my own petroleum tank truck, and hauled for the majors and independent's.
Re: Lawn tractor hard starting [Re: Tom NJ] #4688713
03/08/18 01:55 PM
03/08/18 01:55 PM
Joined: Jan 2013
Posts: 1,923
Texas
WyrTwister Offline
WyrTwister  Offline
Joined: Jan 2013
Posts: 1,923
Texas
Look for a vacuum leak on the intake system .

We have a small B&S with a plastic " tube " that functions as an intake manifold . A loose mounting bolt allowed the " tube " to vibrate until it cracked .

This produced a vacuum leak & the engine would not start until you gave it a shot of fuel . After starting , it ran OK until / unless you shut it off / let it die .

Also , my SOP each spring is to check the air filter and install a new plug . Change oil & drain / fill with new gas .


Wyr
God bless
Re: Lawn tractor hard starting [Re: Tom NJ] #4688718
03/08/18 02:00 PM
03/08/18 02:00 PM
Joined: Apr 2009
Posts: 2,933
Canada
boraticus Offline
boraticus  Offline
Joined: Apr 2009
Posts: 2,933
Canada
How does the machine idle once it's warm? If it won't idle well and if the choke system is working, I'd pull the carb to look at the low speed circuit. The slow speed jet might be obstructed. If so, it's "wire time". Elixers are good at cleaning out your wallet, not so for cleaning carbs.

If it has an engine pulse pressure fuel pump, I'd also check that. Pull the fuel line off of the carb, put the end into a jar or can and spin the engine to see how the fuel flows. Do it when the engine is cold to replicate cold starting conditions. The diaphragms in the pump might be getting weak and not priming the pump as efficiently when cold.

If any of your fuel lines had a hole, you'd definitely be smelling gas.

Once the fuel system has been ruled out, I'd look at the electrics. Try a couple new plugs first. If you have healthy spark on both leads, the next step would be to look at valve clearance.

Let us know when you get it figured out.

Re: Lawn tractor hard starting [Re: Tom NJ] #4688724
03/08/18 02:03 PM
03/08/18 02:03 PM
Joined: Jul 2006
Posts: 2,143
Virginia
Tom NJ Offline OP
Tom NJ  Offline OP
Joined: Jul 2006
Posts: 2,143
Virginia
This model does not have a manual choke. The choke is set automatically, but there a setting on the throttle for cold starts below something like 32F. That said I should be able to see the choke under the filter to see if it is closed when cold. The tractor is at my farm and we'll be going there sometime next week.

Re: Lawn tractor hard starting [Re: Tom NJ] #4688739
03/08/18 02:25 PM
03/08/18 02:25 PM
Joined: Jan 2018
Posts: 67
Missouri
David2431 Offline
David2431  Offline
Joined: Jan 2018
Posts: 67
Missouri
You're doing correctly on keeping away from ethanol gas. Try this before tearing into any mechanical stuff: Add some SEAFOAM to the fuel - try 2 or 3 ounces per gallon of fuel. Stir it around if you're adding it to the fuel tank if you can. I'm a Techron fan myself, but try the Seafoam. Not Chemtool or anything else. Run it as much as possible. Repeat.

I run a John Deere 216 that has 3,000 hours (bought it new - NOT the original motor) and I think I know of what I speak.

The fact that you can run it for over an hour once it starts tells me it's a fuel delivery problem.

BTW, you HAVE cleaned the air filter, correct????

Keep us informed.

Last edited by David2431; 03/08/18 02:27 PM.
Re: Lawn tractor hard starting [Re: Tom NJ] #4688755
03/08/18 02:51 PM
03/08/18 02:51 PM
Joined: Apr 2009
Posts: 2,933
Canada
boraticus Offline
boraticus  Offline
Joined: Apr 2009
Posts: 2,933
Canada
One thing I forgot to mention was checking pulse pressure line from then engine to the fuel pump. If it's leaking or not well connected, that could be a contributing factor.

Re: Lawn tractor hard starting [Re: Tom NJ] #4688759
03/08/18 02:53 PM
03/08/18 02:53 PM
Joined: Jan 2017
Posts: 334
NJ
JLawrence08648 Offline
JLawrence08648  Offline
Joined: Jan 2017
Posts: 334
NJ
Vacuum leak, water in the gas and bottom of fuel bowl, dirty carb replace or clean in an ultrasonic cleaner. Seafoam is great.

Re: Lawn tractor hard starting [Re: Tom NJ] #4688780
03/08/18 03:23 PM
03/08/18 03:23 PM
Joined: Dec 2003
Posts: 9,845
Florida, Cape Coral
Eddie Offline
Eddie  Offline
Joined: Dec 2003
Posts: 9,845
Florida, Cape Coral
I think that with only 3 years mowing a 1+ acre that the hours are probably less than 150 so I think it is not intake/exhaust valve settings. In addition; it sounds like the maintenance is very good so as suggested, fuel delivery could be the problem. I think the choke system or pulsed fuel pump could be the issue. Ed


CX5 Touring 2.5L :-)
Re: Lawn tractor hard starting [Re: Tom NJ] #4688841
03/08/18 04:21 PM
03/08/18 04:21 PM
Joined: Jan 2009
Posts: 13,865
Illinois
tig1 Offline
tig1  Offline
Joined: Jan 2009
Posts: 13,865
Illinois
Tom NJ,
I have a 6 year old B&S with the 21HP engine. Mine blew the head gasket 2 years ago. Very common on B&S engines. The repair guy miss adjusted the exhaust valves and the engine became very hard to start, because the compression release is connected to the exhaust vales. Mine was only 3-4 thou over the .005 clearance and would not allow the CRS to function. Check the clearance.


2007 Ford Fusion 233,000 miles
M1 0-20 EP
2017 Ford Fusion 58K
M1 0-20 EP
10,000 mile OCIs on both engines
M1 ATF and Valvoline LV
M1 10-30 in all OPE
MC filters

Re: Lawn tractor hard starting [Re: Tom NJ] #4688849
03/08/18 04:27 PM
03/08/18 04:27 PM
Joined: Sep 2002
Posts: 4,119
Lakeville, MN
MNgopher Offline
MNgopher  Offline
Joined: Sep 2002
Posts: 4,119
Lakeville, MN
Given that he mentioned it seems to be cranking over at a good speed, I'd suggest that looking at the valve adjustment is probably not the culprit.

We've had lots of fun with valve adjustments on another Briggs powered lawn tractor, and as mentioned, the compression release tied to the valves being adjusted correctly. When the valves are out of adjustment, the engine will generally barely crank once the compression won't release...

Stick to looking at the fuel delivery in particular.

Re: Lawn tractor hard starting [Re: Tom NJ] #4688852
03/08/18 04:30 PM
03/08/18 04:30 PM
Joined: Jun 2012
Posts: 1,724
USA
oldhp Offline
oldhp  Offline
Joined: Jun 2012
Posts: 1,724
USA
Next time it won't start, take the gas cap off. My JD lawn tractor was doing exactly what you describe. The gas cap venting became clogged because of whatever. I made all the vent holes just a tad bigger. Never had a problem after that.


2018 RAM 1500 3.6/8 speed.
2017 Jeep Sahara Unlimited 3.6
"U kan't fixe it......if'n it ain't broke."
Page 1 of 2 1 2

BOB IS THE OIL GUY® Powered by UBB.threads™