The trench compaction equipment commonly seen is the pad foot jumping jack rammer compactor with various widths of pad available as to the job. Govt spec jobs invoke a wide trench with six inches to each side of the pipe, thus a 8" water main will require a min 24" trench so rammers have wide pads; about a foot or so for this work. We have gas, two cycle gas, and a diesel powered one. The diesel version notably seems to hit the hardest and it is a wacker model, I believe DS70 or sim. The explanation as to why the diesel hits hardest is because the diesel engine piston slows dramatically for the compression and once it fires it rapidly accelerates. This differential is the reason the force to the pad foot is greater than say a comparable gasoline model. We noticed the local constabulary of rental yards have no longer kept the diesel in their rental fleet, saying they were good machines but once they went bad they were a pain. (Not sure what that means) Wait until they try a new electronic fuel injected gas machine...but that's another topic. * We were able to get a comparable quotes for a new machine from wacker's dealers so we can have a backup or a pair of these going. I looked around on the web 'for sale' lists in SoCal and found some clean looking vintage gas versions & only one diesel one, but that diesel machine had been through a complete engine overhaul (I always wonder why a machine is provided extensive overhaul then it is sold promptly thereafter - wouldn't it be smarter to invest in the machine and keep it for oneself to retrieve the investment by operating the machine? Sorry to digress). * As to why this post is in the TLB forum, I believe there is no specific section for soil compaction machines and that my previous entries about compaction machines were in the "other compact equipment" category which I suddenly realized is not about compaction....but I figured folks who have TLBs will likely have rammers and be able to lend an opinion about the diesel powered rammer. Thanks.
Since the previous post, I located and purchased a used diesel powered Wacker, a newer model than the one referenced previously. The two cycle machine is on a residential job and they are happy with it 'cause it is light weight (easy to drag around) and easy rope pull to start.
Is the diesel one a rope pull start?
Yes: both diesel models are rope pull start. The earlier one requires a steady pull to the compression stroke, then flip a lever to activate the compression release, then pull the rope to start. The newer one has an automatic compression release where you simply pull the rope and it starts.