• If you like what you see here and your interests are compatible with our 30,000 other users, Welcome. Fill out the registration form with your interests, your real name (seen only by moderators) and your city, state or country. Your account is then manually checked and approved. There is too much funny business on the web for us to do otherwise. Be sure to use a working email address and do not use cloaking or anonymous web connections.

VH4D Wisconsin

Richard F

Registered
This VH4D Wisconsin was made in 1985. This engine is all original. After using it for about 4 hrs recently with no problem or indication of anything going wrong, i was finished my work and turned it off. The next day I started it and it sounded like an old steam jenny. It was huffing, puffing and blowing air pressure out of several places of the head gasket. So I knew instantly that the head gasket had blown. I went ahead and pulled the head off and guess what I find? A hole about the size of a quarter in the top of one of the pistons. In fact, it looked like the piston came up, hit a rock, and busted a hole in the top. These are not light weight components. I am going on replacing the piston and head gasket and whatever else I need to do for repair. And double and triple check everything in that engine. My question is simple, does anyone have any idea what would have caused this??
 

K D Redd

In Memory Of
A hole burnt is a piston normally is a sign of a lean fuel condition. You may see some damage to the other piston but if the cylinder with the damaged piston has it's cooling air block some how this might be also contribute to the cause. I would pull all of the shrouding and make sure ALL cylinder and head cooling fins are not blocked. also be sure the opening to the flywheel is not restricted in some way. I would also check the carb. If the carb has a non-ajustable high speed jet, most I have seen do, make sure the carb is clean and check the float level. If you think the engine is running a little lean you can richen the mixture on a fixed jet carb by raising the float level a bit.

Kent
 

bill chasser

Registered
KD

I agree with Richard on this regarding airflow between the tins and engine. Make sure you clean all debris from the shrouds on a regular maintenance schedule. My vh4d is mounted on a stump grinder which constantly is run in a dirty environment and at extreme angles while processing materials. If yours is not equipped make sure to have screens on the flywheel opening to limit junk being sucked into the flywheel area. Grass, dirt etc will always find a way into the cooling flow and will become lodged more readliy if the engine is oily from leaks. The tins are easily servicable and a pressure washer at your local self serve carwash will cure this issue. Make sure there are no oil leaks and repair them as they arise. And the dirtier the environment, the more often servicing should accomplished ie. I clean my unit after every use.

Also, its been awhile since I've done a teardown but, make sure you oil is clean and filters changed regularly. These engines are a splash and dip along with oiling by sprayers and low oil with extreme engine angles can allow the engine to starve for oil. check the rod bearings for damage and the oiling to the bottom of the pistons. It could be that the piston got hot also from a lack of oil to the underside to cool the piston dome.

Most of these vh4d are used in extreme service conditions and really take a beating. Paving machines are especially prone to eng damage because of the increased heat inherent with the eguipment with added shrouding by the end users manufacturing around the eng itself and again lack of cooling because of junk accumolation under the tins.

I have a vh4d basket case that I use for parts. Should you need any used parts I may be able to help. I am also looking for an electronis regulator for my charging system should any one have one to sell.
 

Top