Hey guys,
Recently ran into a problem with my EG, concerning Rod knock. I was driving around and noticed my oil pressure light flickering. I was on the highway at the time, and so I proceeded to get home as fast as possible. After exiting the highway, I could hear Rod knock, although only when the engine was reving more than like 3k rpms. So I figured, either I must be really low on oil for some reason, or my oil pump is shot. So, I got it home, and the next day changed the oil, cause it was low. Started it up, and it still had rod knock, so now I knew the rod bearings were shot. So, I ordered some new rod bearings from Honda, (yes I ordered the right ones), and replaced the bearings. They all looked ok, except for Cylinder # 3 bearing, which was cracked. I didn't get to thoroughly inspect the rods, as I didn't want to tear the motor apart, and I figured my problem was the bad rod bearing on # 3. So, I re-assembled everything and started it up. It idled fine, and there was no rod knock noise. So I let it warm up and took it out on the road. Same thing, after like 3k rpms, it starts to knock. So I bring it back home, and while it's idling (600 rpms) the low oil pressure light is flickering. So I put it in the garage, and I've been trying to figure out what to do.

A buddy of mine, DSM guy, said that these symptoms are classic DSM symptoms of Crank-walk. Low oil pressure sometimes, and a rod knock.
So my question is, what are some of your suggestions?

The motor is a B16A, with a GSR head and Intake Manifold. I have LS pistons and a GSR tranny. Custom turbo kit, with a 14b. I was thinking about getting a B18a/b block and going LS/VTEC but I would rather stick with a B16 block, just so I don't have to worry about doing the conversion.

I haven't been able to take the motor apart, but it sounds like there is extensive damage to the main bearings and crank, so IMO it would prob be better to start with a good condition used block, than to rebuild this one.
Lemme know what u guys think.
thanks guys

 

How did the crank look where that bearing cracked? More than likely, the crank needs replacement.

 

Good question. I wasn't able to get a good look at the crank, but if it was indeed scored, wouldn't it be cheaper and easier to just get another block, rather than try and replace the crank. Cause even if I replace the crank, then there might be another problem with the main bearings or something.

Here's where I'm heading...
I could either get an engine stand, and tear the motor down over the winter and replace/repair everything that needs to be fixed. (my mechanic bro's preference)
OR
I could spend the money on a used block (be it b16 or LS), and then just replace the block. Perhaps even saving enough to invest in a set of forged pistons.

Which path do you think would be the most cost-effective option? I have the ability to work on it over the entire winter, and I do all my own work, except anything that needs to be done at a machine shop, so I will be saving on the labor end of it.

Basically, here's my line of thinking... The reason why I am looking into getting another block, is cause the one I have has been with me since my swap back in '00. In addition, it has been hydrolocked (#1 rod replaced), has been beaten on (N/A style) for 3 years, then turbo-ed (which blew the ring-lands). Not to mention it has high miles. But, It has run strong all this time, and all maintenance was performed when required or when something broke. So, knowing this, would it be a good idea to try and re-build this block, or get another used one for a couple hundred bucks?

But, there is one more concern, and that is the oil pressure problem. My buddy, A DSM guy, said the prob could be crank walk, a common prob associated with the 2nd gen DSM turbos. Could the crank being scored at cylinder # 3 cause a problem with the low oil pressure? If not, why is the oil pressure low at idle? My original thoughts were the bearing failed because of low oil pressure, due to the engine being low on oil. However, after replacing the bearings, and doing an oil change, the oil pressure light still flickers on idle, yet there is plenty of oil. This leads me to believe there is a problem with the oil pump or oiling system, further enticing me to look for another block, rather than try and fix everything wrong with this one.

Lemme know what you think, and thanks again for the help.

 

If you don't mind the downtime, the most cost effective way to remedy this problem is option 1. The block you are using now can just be overbored and the crank, rods and pistons replaced and it will work just fine. Everything can be fixed.

You can pick up an LS bottom end for dirt cheap, if you are concerned about the downtime.