3412 caterpillar
3412 caterpillar
(OP)
i have cat 3412 natural gas engine, last week when i shut down engine just when l shut down l can hear noise like metal grinding gear teeth, this l hear only on 200 rpm , when is cold engine nothing, so when l start and shut down immediatelly ln can hear this gear like few knocks on front side engine. i
l checked w pump, other pump and dont have clue what can it be, engine is runniong ok, compression ok, to take it apart is not quite option, l am wondering valve lifters or else, it can be hear on front of engine , but noice can be from rear comming, does anybody knows what can it be
l checked w pump, other pump and dont have clue what can it be, engine is runniong ok, compression ok, to take it apart is not quite option, l am wondering valve lifters or else, it can be hear on front of engine , but noice can be from rear comming, does anybody knows what can it be





RE: 3412 caterpillar
RE: 3412 caterpillar
Mike Halloran
Pembroke Pines, FL, USA
RE: 3412 caterpillar
When was the last time you checked valve lash and bridge adjustments? The 3400 series of gas engines have had valve life issues, mainly shows up as excessive wear, valve face and seat on the exhaust valves, is accelerated by not doing valve and bridge adjustments at recommended service intervals. As the get worse in wear we had reports of "funny noises" shortly before dropping a valve. Look at the valve and bridge adjustment screws, all should be about the same, a noticable diffenrence could indicate an excessive wear problem. If you have an older service manual it will tell you that you only need to adjust the valve bridges after an overhaul THIS IS WRONG! Adjust bridges EVERYTIME before adjusting valve lash. Newer manuals should all be correct. Compression will usually test close to the other cylinders until wear gets really bad. Sometimes you can pick up indications of the problem by examining the spark plug. How do they all look?
What is the engine driving? I just had a gas engine genset that had a strange noise at startup and shutdown, turned out to be the generator bearing. Could be something in the driveline or driven equipment.
Hope that helps.
RE: 3412 caterpillar
l am from croatia and I do appreciatte all help from you guys, you are really good people and l thank you a lot, we have 4 3412 gensets working in parallelo on oil rig and all info from you is priceless
marko
RE: 3412 caterpillar
RE: 3412 caterpillar