jstatham 27 Posted June 9, 2022 I just picked up yesterday a 1998 Foreman 400 that I am planning on using for parts. Before I tear down the engine I wanted to see if I could get it to run. Evidentially the starter button went out and the guy butchered the wiring harness trying to get it to run. My question what would be the easiest way to get it to run without taking my wiring harness off my good running machine. Is there a way I could park my good bike beside the bad and make some kind of jumper wires to use my good harness and CDI so I can get it to turn over and possibly crank. The pull start is removed but the starter is there. Any help would be greatly appreciated. I also got another 450 engine in the deal and would like to do the same with it. Share this post Link to post Share on other sites
shadetree 5,969 Posted June 9, 2022 1 hour ago, jstatham said: I just picked up yesterday a 1998 Foreman 400 that I am planning on using for parts. Before I tear down the engine I wanted to see if I could get it to run. Evidentially the starter button went out and the guy butchered the wiring harness trying to get it to run. My question what would be the easiest way to get it to run without taking my wiring harness off my good running machine. Is there a way I could park my good bike beside the bad and make some kind of jumper wires to use my good harness and CDI so I can get it to turn over and possibly crank. The pull start is removed but the starter is there. Any help would be greatly appreciated. I also got another 450 engine in the deal and would like to do the same with it. other than having the wire harness connected the right way ?, you can't take short cuts just to see if the engine will run. start with getting the service manual from our site here, start tracing the butchered wires, and see if you can at least splice in some good wires to the correct harness side to switch or what ever to make a good connection. you need a good neutral light, good ground, kill switch set to center so you do not ground the spark plug coil. oil temp light comes on, goes off when you turn the key on, if ya got all this right ?, it should spark the spark plug. use a VERY SHORT burst of starting fluid just to see it the engine will at least '' hit '' ?. 1 Share this post Link to post Share on other sites
jstatham 27 Posted February 21, 2023 (edited) Well I am finally getting back to this and thought I could use the wiring Harness from the 1996 but they are not the same from what I can tell. I just want to see if this thing will run. I was able to straight wire the starter and got it to turn over. I am going to try and find he manual on this site. Does anyone have any experience doing this? If the motor is good I am going to use for a spare if it is bad I need the head. Edited February 21, 2023 by jstatham Share this post Link to post Share on other sites
jeepwm69 7,719 Posted February 21, 2023 What exactly is different? Looks like the harness itself is 95-96, then 97-98, so the harness itself has different part numbers. That said, the stator, gear position switch, voltage regulator, CDI, fan control module, and coil are all the same, so I would use whichever harness is in better shape. Looks like all the electrical components are the same. Share this post Link to post Share on other sites
shadetree 5,969 Posted February 21, 2023 just looked his yr . model up, wire harness for a 1998 trx400fw only fits the '97- '98 model going by partzilla anyway. Share this post Link to post Share on other sites
jstatham 27 Posted February 22, 2023 I know the gear shift position sensor if different. I started tonight with a volt meter trying to get the light to come on when the switch it on and didn’t make it very far. The leads on my volt meter broke. Almost every wire has been hacked on. It’s a mess. I really don’t want to break down my good 1996 just to see if this motor is good. I’ll work on it this weekend when I am fresh and have some patience. After the day I had at work I didn’t need to mess with it. More to come. Share this post Link to post Share on other sites
shadetree 5,969 Posted February 22, 2023 9 hours ago, jstatham said: I know the gear shift position sensor if different. I started tonight with a volt meter trying to get the light to come on when the switch it on and didn’t make it very far. The leads on my volt meter broke. Almost every wire has been hacked on. It’s a mess. I really don’t want to break down my good 1996 just to see if this motor is good. I’ll work on it this weekend when I am fresh and have some patience. After the day I had at work I didn’t need to mess with it. More to come. hang in there bro..take yer time. we ain't going anywhere...we are here if ya need us :-). 1 Share this post Link to post Share on other sites
jeepwm69 7,719 Posted February 22, 2023 13 hours ago, jstatham said: I know the gear shift position sensor if different. I started tonight with a volt meter trying to get the light to come on when the switch it on and didn’t make it very far. The leads on my volt meter broke. Almost every wire has been hacked on. It’s a mess. I really don’t want to break down my good 1996 just to see if this motor is good. I’ll work on it this weekend when I am fresh and have some patience. After the day I had at work I didn’t need to mess with it. More to come. So is one of them an ES, and one a footshift? Share this post Link to post Share on other sites
toodeep 1,759 Posted February 22, 2023 95/96 didn't have a speedometer like 97+ so there will be some differences in the harness. Everything should be the same enough though to make it just run. Share this post Link to post Share on other sites
jstatham 27 Posted March 2, 2023 Hello everyone. I have been fighting this POS all week. I’m not expert in wiring but everything is cut and hacked up like crazy. Would I be smarter to just take the engine off and set it beside my working one and hook up to its wiring? if it’s compatible? Here is a video I made tonight. If you can’t tell I’m beyond frustrated. This thing is a 1999 I believe Forman 400 and I have a working 1996 Foreman 400. Does anyone have a spare harness I could rent to test it? None of them are electric shift. Share this post Link to post Share on other sites
Goober 1,555 Posted March 2, 2023 nothing much here. Sounds like you’re stuck between wanting the motor for parts or restoring this quad? Share this post Link to post Share on other sites
jstatham 27 Posted March 2, 2023 Yes. My 400 needs a new head because the vale cover bolts are broken and leaks oil. I don’t want to tear it down if the motor is good. If it’s good I will use as a spare. I have all the parts for this quad. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted March 2, 2023 You could Heli-Coil the bad threads , or even go over size by tapping to a USA thread like 1/4" , I have got by on my 300s with that fix , or replace the head , the 400 head is different than the 450 , it will bolt up and fit , but the 450 head is less compression Share this post Link to post Share on other sites
jstatham 27 Posted March 2, 2023 My father in law tried Helicoils and he put them in crooked are they are just spinning. If I am going to break it down I want to go back with something I know is going to work. My good machine was a 400 but I put a 450 piston and jug and a 400 head on it. When I rebuilt it I changed the stickers to 450. 1 Share this post Link to post Share on other sites
Goober 1,555 Posted March 2, 2023 Power Sports Nation has a good looking 97 wire harness for $300 https://www.powersportsnation.com/honda-foreman-400-fw-97-wiring-harness-32100-hm7-611-41018.html 1 Share this post Link to post Share on other sites
toodeep 1,759 Posted March 2, 2023 Was the battery about dead or good in that video? If it was good, that motor is in trouble. Share this post Link to post Share on other sites
jstatham 27 Posted March 2, 2023 I just had it hooked to a 10 amp battery charger. I am just trying to get the Neutral lights to work so I can jump the start button that has been mutilated. Once I get that working I will actually put a battery on it. Share this post Link to post Share on other sites
toodeep 1,759 Posted March 2, 2023 Okay, I was just making sure you wasn't wasting time on something that was bad. With all the aftermarket parts on that machine and the messed up wiring I can see where your having issues. That green connector from the handlebar switch goes to the rear connector, the colors of the wiring should verify that. Next issue is the change switch connector. You showed a 3 prong connector in the video and that should be a 2 prong, the speed sensor would be a 3 prong. Share this post Link to post Share on other sites
shadetree 5,969 Posted March 2, 2023 i'm kinda confused here, if you are just trying to see if the engine will run ?, then why worry about the wire harness ?, its best to fix it with a good harness, then see if it will run ?. if all you are wanting to do in the long run is keep the engine as a spare for the good running bike ?, chances are, you will end up replacing parts on the spare engine anyway !!. in other words, you are wasting your time on that messed up harness. now..if you are wanting to build another running atv out of this project ?..THEN STOP WASTING TIME ON THAT CRAPPY WIRE HARNESS..AND GET A GOOD HARNESS..AND FIX IT RIGHT. ditch the china knock-off c.d.i., ditch the china knock-off spark plug coil..AND ANY OTHER CHINA JUNK YOU ARE BUYING ??..HONDA'S DO NOT LIKE CHINA JUNK !!!. when you are tired up wasting time with it ?, drop it off at my house, leave some cash here..give me a few weeks with it, i'll have it running in no time !.but it won't be with china parts ( that you buy ! )..it will be with the correct parts...and it will run when i am done with it. until then ?, get a good harness, get the correct parts, and fix it the right way. you are just wasting time and money the way you are doing it right now. i am not trying to be hard on you ?..but omg..that harness beg's for shorts everywhere !!. 1 Share this post Link to post Share on other sites
jstatham 27 Posted March 3, 2023 Shade Tree all I am wanting to do is see if it runs before I tear it down but I did make a bunch of progress tonight. I figured out there are actually 2 harness on the bike for some reason. I have no clue why the previous owner did that. Anyway I got it patched up enough to get it to turn over but I have no spark. I have voltage going to the coil and nothing coming out the other end. I checked the coil with the multimeter and no resistance on either terminal. I didn't buy any of the Chinese junk it all came with the bike. I learned the Chinese junk part lesson on my last build. Anyway I am going to take the coil off the other bike this weekend and see what happens. I am kind of on the fence with this bike do I fix it or use for parts. If the motor cranks right up and sounds good I may fix if it smokes and knocks I am not going to waste my time. More to come this weekend. Everyone be safe with the storms coming through. Share this post Link to post Share on other sites
shadetree 5,969 Posted March 3, 2023 2 hours ago, jstatham said: Shade Tree all I am wanting to do is see if it runs before I tear it down but I did make a bunch of progress tonight. I figured out there are actually 2 harness on the bike for some reason. I have no clue why the previous owner did that. Anyway I got it patched up enough to get it to turn over but I have no spark. I have voltage going to the coil and nothing coming out the other end. I checked the coil with the multimeter and no resistance on either terminal. I didn't buy any of the Chinese junk it all came with the bike. I learned the Chinese junk part lesson on my last build. Anyway I am going to take the coil off the other bike this weekend and see what happens. I am kind of on the fence with this bike do I fix it or use for parts. If the motor cranks right up and sounds good I may fix if it smokes and knocks I am not going to waste my time. More to come this weekend. Everyone be safe with the storms coming through. dang it..i had a book typed out, and the web site ate it ?... you better start with a good harness..that one is trash. a pic of a before and after trx400fw i did a few yrs ago. wanna do it right ?..you better spend the money..it wont be cheap !..lol. 2 Share this post Link to post Share on other sites
Goober 1,555 Posted March 3, 2023 Yup that’s what I would do—a restoration. Harnesses might be easier to find than heads. A compression check would tell a lot. but you’d have to use a good battery to get er rotating. Share this post Link to post Share on other sites
jstatham 27 Posted March 3, 2023 11 hours ago, shadetree said: dang it..i had a book typed out, and the web site ate it ?... you better start with a good harness..that one is trash. a pic of a before and after trx400fw i did a few yrs ago. wanna do it right ?..you better spend the money..it wont be cheap !..lol. Thanks Shade Tree that bike looks sweet. I rebuilt one last year for my daughter and learned the hard way on the cheap parts. I'll will let you know what happens. 1 Share this post Link to post Share on other sites
shadetree 5,969 Posted March 3, 2023 27 minutes ago, jstatham said: Thanks Shade Tree that bike looks sweet. I rebuilt one last year for my daughter and learned the hard way on the cheap parts. I'll will let you know what happens. i hate to burst yer bubble ^^^^, but the tires are mounted on the rims backwards ?, or you mounted them on the wrong sides ?..lol. the tread pattern looks backwards ?. Share this post Link to post Share on other sites
jstatham 27 Posted March 3, 2023 ok I will check it out. Hello everyone. I have been fighting this POS all week. I’m not expert in wiring but everything is cut and hacked up like crazy. Would I be smarter to just take the engine off and set it beside my working one and hook up to its wiring? if it’s compatible? Here is a video I made tonight. If you can’t tell I’m beyond frustrated. This thing is a 1999 I believe Forman 400 and I have a working 1996 Foreman 400. Does anyone have a spare harness I could rent to test it? None of them are electric shift. Share this post Link to post Share on other sites