Nitroaddict

There has been alot of concern regarding the premature wear issues the new VZ-B is having. It seems that due to the manufacturing process regarding the new piston, that these engines have an extremely reduced lifespan of only slightly more than a gallon of fuel, even when run at moderate needle settings.

Can OS Max support please advise on what steps are being taken to remedy this problem?

Bax

My Feedback: (11)

O.S. has told us that they've not really seen a difficulty, but are investigating things based upon comments on the various R/C car web forums.

Too many factors go into engine wear. We're advising O.S. of all the threads reporting on the topic, and they'll respond with what they see. We're also sending them engines and/or piston/cylinder assemblies that have the claimed problem...as many as we can get.

They will not give any answer until they either find a problem and give a solution, or say there isn't a problem. We're sorry, but we have to wait on O.S.

Nitroaddict

Unfortunately, this is the same answer that I have received from OS when I emailed them directly. This is unacceptable and has caused me to shift all four of my current race engines from OS to another competing brand. I have been keeping a tally, and at this time, I have personally seen, been emailed, posted, or otherwise been informed of 41 different people who have had problems with this engine. This is not a coincidence and is proven by the fact that the OS distributors are accepting returns on this engine, such as Great Planes. Currently, on ever message board I subscribe to, there is at least one post with someone describing the same problem regarding the OS .21VZ-B.

DP-Buggyboy

It seems this is not limited to just the VZ-B. It is a commonly known issue with TM-18 and TZ-18 engines. So much so that RD-Racing Products is producing a wristpin spacer that keeps the connecting rod from contacting the backplate.

Recently, I discovered it is happening with my FS-52 as well. Check this forum post over at my home forum for pictures:
http://www.rcccs.com/index.php?showt...ndpost&p=12435

After about 6 gallons, it had worn the rod, backplate, and started to dig into the engine case. It needs at bare-minimum, a new rod.

I have to mention I am not using the engine for what it was designed for. It's in a monster truck, has FS40-C valve springs and cam, a .21 carb, and a Surpass 90 exhaust, so it spins almost twice the rated ~13,000RPM. In this application, it has been extremely reliable and VERY competitive in a racing environment, despite the excessive bottom-end rod wear.

I have access to a lathe, so I will be making a wrist pin spacer for it to fix this problem and will test it with a new rod next race season.

What I am curious about is if anyone has seen this happen with an unmodified FS engine.