630 Repower

Help Support SkidSteer Forum:

ancomcabs

Well-known member
Joined
Nov 3, 2011
Messages
299
Having trouble with my VH4D and if I can't get it sorted out I am going to consider a re-power with a new 35hp vanguard. There are kits available that should make it easy. My question is has anyone out there done a similar conversion and if so have you been happy with the performance results Thanks in advance
 

jerry

Well-known member
Joined
May 3, 2007
Messages
2,043
I have never been much on additives but try a can of seafoam in it. Sure made a difference on a 610 I had. If you put a outboard squeeze bulb in the gas line it makes the first start in the day much quicker , heat from the engine must evaporate the gas in the carb after shutdown on them.
 
OP
OP
ancomcabs

ancomcabs

Well-known member
Joined
Nov 3, 2011
Messages
299
I have never been much on additives but try a can of seafoam in it. Sure made a difference on a 610 I had. If you put a outboard squeeze bulb in the gas line it makes the first start in the day much quicker , heat from the engine must evaporate the gas in the carb after shutdown on them.
Jerry thanks for the tip. Mine starts fine (winter or summer) I'm having trouble keeping it running now that the weather is warmer. Hoping it is vapor lock that I can cure as I've heard these engines can be prone to it. But if the problem runs deeper and would require major engine work or a rebuild I've been looking into re-powering. The machine is just for personal use as well as snow removal at my business but if I can't keep it running more than a half an hour or so in the summer I've got to do something.
 

Tazza

Moderator
Staff member
Joined
Dec 7, 2004
Messages
16,829
Jerry thanks for the tip. Mine starts fine (winter or summer) I'm having trouble keeping it running now that the weather is warmer. Hoping it is vapor lock that I can cure as I've heard these engines can be prone to it. But if the problem runs deeper and would require major engine work or a rebuild I've been looking into re-powering. The machine is just for personal use as well as snow removal at my business but if I can't keep it running more than a half an hour or so in the summer I've got to do something.
When it's cold, does it start and run well?
If its only when it hot, it has to be electrcial or fuel.
What happens when its hot? does it just run rough or simply quits? Condensors can be heat sensitive, causing a weird spark or even dropping sparks. How is the fuel line routed to the engine? can you keep it away from hot areas? possibly prevent vapor lock, if that is indeed what the problem is.
The thing is, if when cold you have lots of power and starts easily, there is no reason to suspect the engine is worn out and may be able to be fixed far cheaper than feeding it another engine.
 
OP
OP
ancomcabs

ancomcabs

Well-known member
Joined
Nov 3, 2011
Messages
299
When it's cold, does it start and run well?
If its only when it hot, it has to be electrcial or fuel.
What happens when its hot? does it just run rough or simply quits? Condensors can be heat sensitive, causing a weird spark or even dropping sparks. How is the fuel line routed to the engine? can you keep it away from hot areas? possibly prevent vapor lock, if that is indeed what the problem is.
The thing is, if when cold you have lots of power and starts easily, there is no reason to suspect the engine is worn out and may be able to be fixed far cheaper than feeding it another engine.
Tazza The problem has surfaced now that warmer weather is here. When cold it starts easy and runs well (at least as well as I can expect from a 35 year old motor). Last two times I've used it after about a half hour or so it would slowly sputter and die, fooling with the choke would help slightly but only for another minute or so then it would die. After allowing it to sit for a while it could be started again but with a little more difficulty but then it would eventually die again. It has the electronic ignition so I don't think the condenser is the problem. I leaning towards thinking vapor lock, I have pulled the fuel line away from the engine as much as possible and am going to fab a simple heat shield to try and help keep the carb cooler. There is also a service to the manifold that involves making a hack saw cut between the intake and exhaust side to help keep heat from transferring over. I'm going to insulate the fuel line as well to see if that helps. The other thing that concerns me is maybe the engine is just running hotter than it should and that is why the vapor lock issue? If so why is it running hot? Oil has been recently changed and is full, fins have been cleaned out and all metal shrouds are in place. Any idea what the temperature of the engine should be when running, I could check it in various places with an infrared thermometer next time I use it. I'm not eager to spend money if I don't have to but am just looking into all my options should the heat issue be due to an expensive internal problem
 

Tazza

Moderator
Staff member
Joined
Dec 7, 2004
Messages
16,829
Tazza The problem has surfaced now that warmer weather is here. When cold it starts easy and runs well (at least as well as I can expect from a 35 year old motor). Last two times I've used it after about a half hour or so it would slowly sputter and die, fooling with the choke would help slightly but only for another minute or so then it would die. After allowing it to sit for a while it could be started again but with a little more difficulty but then it would eventually die again. It has the electronic ignition so I don't think the condenser is the problem. I leaning towards thinking vapor lock, I have pulled the fuel line away from the engine as much as possible and am going to fab a simple heat shield to try and help keep the carb cooler. There is also a service to the manifold that involves making a hack saw cut between the intake and exhaust side to help keep heat from transferring over. I'm going to insulate the fuel line as well to see if that helps. The other thing that concerns me is maybe the engine is just running hotter than it should and that is why the vapor lock issue? If so why is it running hot? Oil has been recently changed and is full, fins have been cleaned out and all metal shrouds are in place. Any idea what the temperature of the engine should be when running, I could check it in various places with an infrared thermometer next time I use it. I'm not eager to spend money if I don't have to but am just looking into all my options should the heat issue be due to an expensive internal problem
It does sound like vapor lock. How is the fuel pumped to it? could it be faulty not pumping enough fuel when it warms up? If you can install a hand primer in the line, when it stalls out, can you give the primer a good squeeze and try and start it? it should push fuel past the vapor lock if it is indeed doing that?
If its getting too hot, it could be running lean, so it needs adjusting to give it a little more fuel.
 
OP
OP
ancomcabs

ancomcabs

Well-known member
Joined
Nov 3, 2011
Messages
299
It does sound like vapor lock. How is the fuel pumped to it? could it be faulty not pumping enough fuel when it warms up? If you can install a hand primer in the line, when it stalls out, can you give the primer a good squeeze and try and start it? it should push fuel past the vapor lock if it is indeed doing that?
If its getting too hot, it could be running lean, so it needs adjusting to give it a little more fuel.
It's got a mechanical fuel pump, could be weak for all I know. I can check the plugs to see if there are signs of running lean and make that adjustment too Thanks Taz
 

Latest posts

Top