Discussion:
Wont start at times

This Komatsu FG18HT-17, serial number 670347A with a 3.0 Mazda engine in it will crank all day long with multiple spits and sputters like it is going to start, only to go back to cranking. Had a bad cam and crank sensor when I first looked at it along with the codes to confirm that. I have since replaced the crank sensor two more times, the last time with a special metallic sensor that was supposed to fix this issue. I have also replaced the main injector and the fuel pressure sensor. When it is cranking, it will not start with any type of starting aid so I think fuel is not the issue. I am getting good spark and the engine will start at times, and it runs really good when it does start. Any help would be greatly appreciated. Thanks.
  • Posted 27 May 2015 11:44
  • By lvscr
  • joined 24 Apr'14 - 41 messages
  • Idaho, United States
Showing items 1 - 9 of 9 results.
Glad to hear it!
  • Posted 30 Jul 2015 20:47
  • By Jeff
  • joined 8 Feb'07 - 60 messages
  • Georgia, United States
There is nothing worse than a sharp image of a fuzzy concept.
-Ansel Adams
The OEM can and crank sensors did the trick. Thanks for all your help. We followed the bulletin and used those part numbers.
  • Posted 30 Jul 2015 10:33
  • By lvscr
  • joined 24 Apr'14 - 41 messages
  • Idaho, United States
well i stand corrected then
i just checked a cat bulletin about spark plugs and they are NGK.. DOH!
not sure where i saw that about the denso plugs
maybe i was confusing it with the mitsu engines in the older cat trucks.
my mistake
  • Posted 26 Jun 2015 00:37
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
Swoop,

The Nissan K21 and K25 engines all come with NGK FR2B-D plugs.
There is a tech bulletin put out by Nissan not to use anything but NGK FR2B-D plugs as they have the last few threads removed so that they do not pull the threads out of the head due to build up of carbon.

Denso does not produce a plug with the threads removed and in the heat range that the NGK is.
  • Posted 26 Jun 2015 00:15
  • By Partsguy5
  • joined 13 Jun'12 - 409 messages
  • California, United States
I'll have to agree with jeff on the fact that these trucks did come with a nissan engine and on the plugs, all nissan engies come with Denso (nippondenso) plugs in them. NGK plugs may work but they are not OEM plugs.
As for the sensors for the crank and cam i also agree they should be replaced as a set, and if at all possible try to use OEM replacement parts. And to add to any errors that throw the POS cam phase or crank codes you might want to check the EGI and main C relays, they can also interrupt the signal for those sensors and cause a misleading error that will run you in circles and replacing parts that don't need replacement.
just some facts to consider while troubleshooting :o)
  • Posted 26 Jun 2015 00:01
  • Modified 26 Jun 2015 00:02 by poster
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
First this truck has a Nissan (now GCT) K21 Engine (not a Mazda 3.0) from the factory. Yes there was a problem with crank/cam sensors. A Parts & Service News was published in May 2013 (FT13004). The New Crank Sensor is 23731-6N21A & New Cam Sensor is 23731-6J90C. Its important to replace them as a set with the new ones.
  • Posted 25 Jun 2015 21:02
  • Modified 25 Jun 2015 21:03 by poster
  • By Jeff
  • joined 8 Feb'07 - 60 messages
  • Georgia, United States
There is nothing worse than a sharp image of a fuzzy concept.
-Ansel Adams
NGK?
is that what comes in these from the factory? if so then i guess we can say it probably isnt the plugs as long as they are gapped correctly.

So when it does run it runs good but when it acts up nothing will get it to run. Replacing the crank sensor fixed it in the past, now it has a metallic sensor. Have you gone back and rechecked this sensor to see if it is failing? or checked the cam sensor? (i'm sure you have)
Have you checked the timing to make sure it is staying in time? It might be a key or something could have sheered and is slipping causing the engine to get out of time occasionally causing this failure. It seems unlikely but i'm thinking outside of the normal box now.
As long as you know you are getting spark, air, and fuel then it would seem likely to look at other possibilities that could cause this.
  • Posted 28 May 2015 21:23
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
We put NGK's in it.
  • Posted 28 May 2015 05:56
  • By lvscr
  • joined 24 Apr'14 - 41 messages
  • Idaho, United States
i know this sounds crazy but what spark plugs are in it?
OEM or some knockoff brand like champion or autolite?
I've ran across problems like this that wound up being the spark plugs not being OEM plugs and the truck would give problems like this.
  • Posted 27 May 2015 21:37
  • Modified 27 May 2015 21:38 by poster
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com

Post your Reply

Forkliftaction accepts no responsibility for forum content and requires forum participants to adhere to our rules of conduct. Click here for more information.

If you are having trouble using the Discussion Forums, please contact us for help.

Movers & Shakers
Jeannette Walker Jeannette Walker
CEO, MHEDA
President, European Rental Association (ERA)
Chief marketing officer, JLT Mobile Computers
Chief executive officer, East Penn Manufacturing
Latest job alerts …
Saratoga, United States
East Syracuse, United States
Columbia, SC, United States
Indianapolis, IN, United States
JLG 260MRT
JLG 260MRT 2016
Flesherton, Ontario, Canada
Used - Sale
JLG 600AJ
JLG 600AJ 2012
Flesherton, Ontario, Canada
Used - Sale

PREMIUM business

Bolzoni SpA (Group HQ)
Manufacturer of Lift Truck Attachments, Forks and Lift Tables, with the most extensive range in the market.
Fact of the week
The use of "hello" as a telephone greeting is attributed to Thomas Edison. He is said to have suggested it as a simpler alternative to other greetings, such as "Do I get you?" or "Are you there?".