Rjohn 4 Posted February 12, 2022 Had the 07 Honda 400 out ice fishing on way in I noticed it was in limp mode I had 2km to go so brought her in slow. Was running good then all sudden a pop from front and she stopped instantly shutting off no start and can't pull her over stuck.. rolls in neutral easy I can select all gears but I believe she's toast.. guessing the crank broke anybody have any thoughts. She has oil I haven't read the limp mode code it was raining and cold fishin sucked aswell.. Share this post Link to post Share on other sites
toodeep 1,759 Posted February 12, 2022 I would start with removing the rope starter and try to move the crankshaft with the bolt. A little back and forth to see if whatever happened will come loose. Any weird noises before the "pop"? 1 Share this post Link to post Share on other sites
Rjohn 4 Posted February 12, 2022 1 hour ago, toodeep said: I would start with removing the rope starter and try to move the crankshaft with the bolt. A little back and forth to see if whatever happened will come loose. Any weird noises before the "pop"? No weird noises just was in limp mode then just a pop and a clank . everything just stopped instantly I was going about 15km hr. The quad was working great all day but on my way in I noticed esp limp mode was on then she was a tow in.. Share this post Link to post Share on other sites
Goober 1,555 Posted February 12, 2022 (edited) Pull valve cover and inspect valve condition. Maybe dropped a valve. Don’t try to roll it over anymore til you see all valves are in place Edited February 12, 2022 by Goober Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 On 2/11/2022 at 11:25 PM, Goober said: Pull valve cover and inspect valve condition. Maybe dropped a valve. Don’t try to roll it over anymore til you see all valves are in place So I got Time during cooking burgs on the barbie. I ripped all plastics,tank off then tore top valve cover off...so something dynamited lol I grabbed onto valves and springs I couldn't get them out by hand so not sure if they broke...but not ruled out yet I gotta take head off still.. here's the pics of the spark plug that is gone lol. lookin in spark plug hole its alot of aluminium shavings so not great Share this post Link to post Share on other sites
Fishfiles 20,147 Posted February 15, 2022 Hi Rjohn , from looking at that plug , I would guess you have severe piston damage , a compression test or even a finger over the spark plug hole might confirm that 1 Share this post Link to post Share on other sites
Goober 1,555 Posted February 15, 2022 No easy fix there. May as well remove the cylinder head. Plug looks overheated. Insulator core is missing and conductor misshaped. Could have happened by impact too Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 2 minutes ago, Goober said: No easy fix there. May as well remove the cylinder head. Plug looks overheated. Insulator core is missing and conductor misshaped. Could have happened by impact too Hopefully next couple days get head off I just hope bottom end is ok.. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted February 15, 2022 Sounds like you know the lower end importance , if the crank is loose , the upper rebuild won't last long , if it has been sunk , or , if the piston is damaged and lets fragents go into the case , then it should be split and cleaned out or it won't last long as long as it could have , if done right Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 7 minutes ago, Fishfiles said: Sounds like you know the lower end importance , if the crank is loose , the upper rebuild won't last long , if it has been sunk , or , if the piston is damaged and lets fragents go into the case , then it should be split and cleaned out or it won't last long as long as it could have , if done right I do know if ! gets past rings then iam into it lol. I have only rebuilt one motor and it was a old Onan motor. but the Honda shouldn't be to crazy from the opposed Onan.. hopefully Honda parts are cheaper lol than Onan parts... Share this post Link to post Share on other sites
ATC4ever 1,084 Posted February 15, 2022 The cyl & top arent too bad, but if you have to remove the bottom, you will be busy for a while, so make your burgers now 😆 1 1 Share this post Link to post Share on other sites
jeepwm69 7,719 Posted February 15, 2022 1 hour ago, Rjohn said: I do know if ! gets past rings then iam into it lol. I have only rebuilt one motor and it was a old Onan motor. but the Honda shouldn't be to crazy from the opposed Onan.. hopefully Honda parts are cheaper lol than Onan parts... Nothing is cheap anymore, but Honda parts are less expensive than most brands. Rocky Mountain ATV or Honda East Toledo seem to be the cheapest. You can also look at used OEM parts from places like Powersportsnation depending on what you need. If your crank is bad, Vince at Mr Crankshaft and rebuild your old crank for 1/2 to a 1/3 of what a new OEM crank costs. He uses good Japanese Vesrah connecting rods. 1 Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 1 hour ago, ATC4ever said: The cyl & top arent too bad, but if you have to remove the bottom, you will be busy for a while, so make your burgers now 😆 Have to break out smoker for that lol. I made those burgers slowly, during Valentine's Day. wife was like wht u doin... Aaaah burning old stuff off grill and then making burgs 🤣 no iam not in garage 🤣 1 2 Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 44 minutes ago, jeepwm69 said: Nothing is cheap anymore, but Honda parts are less expensive than most brands. Rocky Mountain ATV or Honda East Toledo seem to be the cheapest. You can also look at used OEM parts from places like Powersportsnation depending on what you need. If your crank is bad, Vince at Mr Crankshaft and rebuild your old crank for 1/2 to a 1/3 of what a new OEM crank costs. He uses good Japanese Vesrah connecting rods. Appreciate all the info 🤞on crank lol. I do know one thing nothin but OEM parts on my stuff especially internals there's a reason it runs forever... Honda. Share this post Link to post Share on other sites
Goober 1,555 Posted February 15, 2022 (edited) Did you notice if engine was very hot when it quit? distorted plastic or other heat damage? Smoking from engine surfaces? Edited February 15, 2022 by Goober Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 6 minutes ago, Goober said: Did you notice if engine was very hot when it quit? distorted plastic or other heat damage? Smoking from engine surfaces? Never noticed excessive heat but these are some facts lol quad was a old cn railway unit it's has 20thous km.. it seemed underpowered like 45km max speed.fan was rigged to come on when switch is on ie key.. yes it's a toggle switch 🤣 the oil light was on but had oil ... And just before she went, limp mode kicked on speed dropped to 15km then boom after about 5 min trying to get back to shore.. Share this post Link to post Share on other sites
jeepwm69 7,719 Posted February 15, 2022 Holy crap I can't believe a 400 Rancher held up that long if you were working it like that! The 400's with the Hondamatics were known for having problems if worked hard or modded for big heavy wheels and tires. They tended to burn up clutches if modified in any way or worked hard, especially if ridden in auto mode a lot. But it was usually Hondamatic/clutch issues. What you have seems to be top end/oil starvation issue. 1 Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 7 minutes ago, jeepwm69 said: Holy crap I can't believe a 400 Rancher held up that long if you were working it like that! The 400's with the Hondamatics were known for having problems if worked hard or modded for big heavy wheels and tires. They tended to burn up clutches if modified in any way or worked hard, especially if ridden in auto mode a lot. But it was usually Hondamatic/clutch issues. What you have seems to be top end/oil starvation issue. Ya iam thinking the oil wasn't gettin to the top perhaps oil pump failure.. the more i think about it... She's probably gonna have to be split and inspected.. check pump ect.. I will have to print manual out start reading up on the old girl... If I get a chance I will post pics of hours and kms Share this post Link to post Share on other sites
jeepwm69 7,719 Posted February 15, 2022 I just hope the Hondamatic is ok. It's oil pressure driven and replacements are $$$$ (yeah, that's a 4th, as in thousand, dollar sign) Share this post Link to post Share on other sites
Rjohn 4 Posted February 15, 2022 16 minutes ago, jeepwm69 said: I just hope the Hondamatic is ok. It's oil pressure driven and replacements are $$$$ (yeah, that's a 4th, as in thousand, dollar sign) Ya depression could set in.. Share this post Link to post Share on other sites
Rjohn 4 Posted February 20, 2022 So tore into her today and she dropped a exh valve... Heads has alot of damage I believe she'll need to be replaced.piston has a hole through it.. cylinder has some small nicks not to deep not sure if I can save it. With the hole through the piston I decided to take motor out to go through to check everything and clean. I got motor out so far just need to clean up bench ect..what's best place to buy a head and piston or brand.. located in Ontario canada 1 1 Share this post Link to post Share on other sites
Rjohn 4 Posted February 21, 2022 Well easy parts done.. she's sitting on bench, time to tear into it and check specs. Source a top end hopefully bottom is ok gotta check can chain ect Share this post Link to post Share on other sites
toodeep 1,759 Posted February 21, 2022 When I get done with the project I'm doing I might possibly have a few needed parts. I still have to tear down the donor motor to see what else is good beside the crankcase I need Share this post Link to post Share on other sites
Rjohn 4 Posted February 21, 2022 24 minutes ago, toodeep said: When I get done with the project I'm doing I might possibly have a few needed parts. I still have to tear down the donor motor to see what else is good beside the crankcase I need sounds good to me! Share this post Link to post Share on other sites
Rjohn 4 Posted February 24, 2022 So I got some prices from Honda for piston it's 110 for standard or oversized, rings are more money for oversized though... Crank is alot hopefully mine is ok.. I removed piston and connecting rod looks straight but it is blue and so is crank is this ok? There is a little side play but no play up and down tight. Piston is beat 🤣. Iam still breaking everything down just need to read and watch more vids before I get ahead of myself. Currently searching for used head... Anyone got one? Valves and spring are very cheap I was happy on that price Share this post Link to post Share on other sites