OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Honda Engines New GXV390 hard to start

The new GXV390 on my refurbished slasher is hard to start. No problem with a small squirt of "Start ya Bastard" and it will restart when warm but not after 5 minutes or more. Is there some tuning or adjustment needed? Would stale fuel cause the problem? The fuel is probably 4 months old but it runs the chain saw and whipper snipper in 2 stroke mix OK.

How does the choke work on this engine? Is it fully closing when activated?

I would have thought some sort of adjusment or its something to do with an emissions setting and its too lean to catch on.

You could try it with the air cleaner off as well.
This is an issue with a lot of the chinese copies of the smaller engines, they are just too lean air wise and starting you cant pull enough through the filter.
What sort of filter is it, id assume paper cartrige, but if its oiled foam it might be over oiled.

Ether starting agents are bad news.



This could be a good question for the HPE dealer you bought it off.

Within reason, age is not a problem for Australian petrol as long as it does not contain ethanol. The usual reason for hard starting with Honda engines is that the speed control cable and the ultra-complex linkage on the side of the engine near the carburetor is not closing the choke properly. That is especially true if it will start with priming (even priming with an engine-ruining substance, in this case).

Just remove the air cleaner, put the speed control all the way into the choke position, and look to see if the choke is completely closed. If it is not, you need to adjust both the clamp at the bottom end of the speed control cable, and the adjustment nut at the top of the same cable, so that you get both full choke at one end of the movement, and operation of the kill switch at the other end of the movement. It is a simple adjustment, takes about 2 minutes if you haven't done it before, less if you have.

Some Honda engines have a screw adjustment on the complex linkage that sets how far the choke is allowed to close.

If all of that is not clear, post some pictures of your linkage and we can try to translate all of this to suit your relatively large Honda.

There is one other point worth knowing about cold-starting Hondas. If you want the engine to be easy to start, do not run the carburetor dry when you finish using the engine. If you do, it will probably take 3 or 4 pulls to suck fuel through the various carburetor passages and get it to start.

Thanks Grumpy - that makes some sense - better than the manual that talks about the preset emmission control settings that must not be tampered with otherwise illegel emmissions can result and the legislators in California will track me down and throw me in jail ( or words to that effect) .. goes on to say if you experience hard starting ( first item on the list) return the engine to the Honda Dealer for adjustment .....yeah right.

To quote Allan Sherman, "If unsatisfactory you must take this to the factory but the factory's in Japan so rots of ruck."

Tried starting with no air filter - no better
adjusted cable position and got about 1mm more movement - no better
Tried to take off air filer holder/elbow - no budge - as far as I can make out only 2 nuts holding it on but even getting a screw driver between the surfaces it won't move just keeps springing back - plastic joining to metal- can see/feel all round and sure there are no more points of attachment. - need a parts manual I think

Just paid $US15 to download the Service Manual for the GXV390 to get this information



At least I know what does what now

I would be talking to honda.

If i can get a G300 thats spent 7 years sitting under a house down by the sea with no air cleaner on it to start on the first pull with the stale fuel that was in the tank id say between now and then they have done something wrong.

Note that the pilot screw is actually the idle mixture adjustment, and it has only a small effect anyway. If you have idle problems, it may be worth investigating, but it has nothing to do with cold starting problems.

If the air filter will not slide out easily on the carburetor mounting studs when you remove the two nuts, it sounds as if there is a retaining screw, which could be below the body of the air filter, toward the right from those two mounting studs, or perhaps inside the air filter housing, extending through it.

Here is the short-form workshop manual:

http://www.honda-engines-eu.com/en/images/114198.pdf

If you check the movement of the Choke Rod and the Choke Joint Lever when you put the speed control lever into the choke position, you can see how far they move. You should also be able to flex the Choke Rod slightly without bending it, to see if the choke lever on the top of the carburetor is capable of moving further when the speed control lever is against its stop.

OK it was the old 3rd bolt completely covered by the fuel tap lever when in the open position trick.

Still couldn't get it right off due to the mower handle being in the way but enough to see the choke and it is not even working. When I push the lever into the choke position the throttle linkage is supposed to pick up the choke linkage and take it with it but it is too short to reach swings right past it and I'm blowed if I can see any way to close the gap - the engagement tab needs to be longer by about 2mm - it's as though there is something missing but the manual doesn't show it.




If I hold the choke against the stop with a screw driver it starts first kick from dead cold - like it should. Email sent to Honda

If that is a new engine, it must have a warranty from Honda. If so, you need to contact them and get this sorted out. I can't tell from the picture what is happening, but if you are pushing the speed control all the way forward, across the strong detent so it clicks into the choke position, and the choke isn't closing, then something is wrong. The linkage should snap right forward and touch the choke stop screw. Modifying a brand new engine to make it work is a dumb idea: it needs to be made to work the way Honda intended.

The concern I keep coming back to, is whether you are putting the speed control lever all the way forward past the choke detent. Both the choke and stop positions are relatively difficult to engage - this is done deliberately so you won't kill the engine when you are in the middle of a job. Usually there is a clear marking on the speed control, showing the choke and stop positions at opposite ends. The lever reaches all the way to those positions, if you cross the detents at both ends as you are supposed to.

Got nowhere with Honda - even sent the above photo - they sent back the manual which I have (user manual came in the box) and said if it has been modified from the manual then I have to to take it up with the OEM. I explained I purchased it from a Honda dealer who ordered it in and it was sent on to me in the original un-opened Honda packaging . Their response was if it was pre-delivered by the dealer then it has been damaged in transit - if it wasn't pre-delivered by the dealer return it to the dealer for pre-delivery service to reveal any defect

Just noticed the other night - after closing - the local car dealer is a Honda dealer and has a GXV390 sitting on his shelf - will go and look how it is supposed to be set-up.

Looking at a known good one is just about always the quickest way to find out what is wrong, David, so that seems to be heading in the right direction. There is a very good chance the engine you bought did not receive its predelivery inspection, which I think is what Honda was hinting at. Once you know what is wrong, asking the dealer who sold it to you to put it right on warranty seems to be the solution here. That way you come out of it with the warranty still in operation.

Hmmm.......the "known good one" is exactly the same. Did learn there is another tab further up that the throttle picks up to operate the choke but the throttle only hits it about 1mm from the end of its travel and doesn't move the choke anywhere near enough to close it.

Salesman didn't know anything about it and the mechanic was away.

A smaller engine next to it with a different but similar carbureter/linkage set up was very definate in its choke operation.

Did also learn that any dealer can look at it under warranty and I don't have to return it to the online dealer I purchased it from in NSW.

That would be a little bit embarassing if Honda relasesd a whole batch of engines with the same faulty setup. And you think they would know about it by now.

I would handball it to the nearest dealer.

SORTED - Spoke with the mechanic at the local dealership as we looked at the example on their shelf. Turns out the choke return sping is way stiff and you virtually can't pull against it with finger pressure on the throttle lever. Mechanic said he nearly always replaces the spring with one with less tension - also I need to hook the choke cable onto the lower of the two holes on the throttle lever to give that little extra travel.

So, you were not managing to get the speed control lever to snap across to the choke position? With the small Honda push-mower engines there are sometimes problems with people doing that: if they are not shown how to do it, they may not feel comfortable pushing that hard on a plastic lever. The problem may be worse with a larger engine.

I doubt it is necessary to change Honda's design by using a lighter torsion spring under the choke bellcrank, and I would not do so myself, but of course this is your engine. The first time you set up the speed control lever on a Honda, and get the choke at one end of the travel, and the kill switch at the other end, working precisely as you want, is a learning process. So far I have found them comfortable to use once I have set them up and then used them a couple of times - in fact I prefer them to the Briggs controls which have no detents so you are never quite sure where the choking and killing are going to happen.

Since you now have the engine working to your satisfaction, I'll close this thread.