93 B2600i balance shafts/timing chain noise????

[originalmazdawg]

I have a '93 B2600i 2WD 5-spd. It just started making a rattling noise similiar to clicking lifters. The sound is coming from the front most part of the engine where the timing and balance shaft chains are located. I am suspecting the balance shaft chain, because it seems to be running fine. I heard that the oil pump is driven by this chain, is that true? I need my truck for work, and I really would like to drive it at least until the weekend when I will have time to tear into and find out more. If the oil pump is driven by this chain, then I dont think driving it would be a good idea. So does it drive the oil pump? If not, what else will happen if I continue to drive with this noise coming from my engine?

[Tyranitar]

I would suspect that is is the lifters. My advise to correct it is to start off with a good decarb. Get a can of Seafoam, and draw it into the engine through a vacuum line. have an assistant try to maintain about 2000 rpm and add the Seafoam slowly. The engine will probably try to kill. After you have drawn in at least a third of the can, turn the engine off. Let it set for 30 - 45 minutes and reconnect the vacuum lines. Run the engine till the smoke clears. Now change the engine oil. Use the correct weight oil, and the 5 true synthetic oils often help. For most parts of the country, 5w30 is a good overall weight oil. It works well both summer and winter. Replace the oil filter while you are at it, and make sure it is a high quality filter with a check valve inside. Wix and Purolator are good filters. Fram is not suitable for this application, it has not check valve and they shed fibers that can get into the lifter passages.

[originalmazdawg]

Tyr.. I wish it were the lifters. I have heard the lifters plenty of times after I left me truck sit for two or more days (over the weekend). I would start it and hear the lifters nice and loud until they get "primed". I ran some seafoam in the crankcase and it did help with the noise, it does not happen as much anymore. This time, the noise is not coming from the valve cover, it is coming from the front by the crankshaft pulley or harm. balancer. Any comments on what on the front of the engine is capable of making these noises? Thanks for your reply! L8RS!!

[originalmazdawg]

Turned out to be some slack in the balance shaft chain. The amount of work it took to get to the dang thing was absolutely ridiculous! Oh well, I love my Mazda!! LOL..........L8RS!!