DIY Catch can for the LV3 4.3 V6

WHITESSTOWPIG · August 29, 2019

I occasionally see guys ask about catch cans for the 4.3 so I am putting this out there hoping they will run across this in the future.Currently there is no catch can directly for this application however for DIYers like myself the Elite can kit for the 5.3 V8 in the Silverado will also work.You would just need to purchase some 3/8" hose and a few 3/8" hose clamps.A catch can is probably not absolutely needed in this application but for the OCD guys who occasionally ask the information is now out there for you.

Grumpy Bear · August 29, 2019

That is a nice job you did there. The 4.3 is the redheaded stepchild that gets no love. Thanks.....

Doublebase · August 30, 2019

There's no catch can for the 4.3? I always figured any catch can would work with 3/8's hose and a couple clamps.

My thought on catch cans is this...they don't hurt anything as long as you empty them. And they probably help.

WHITESSTOWPIG · August 30, 2019

Couldnt agree more.Also one could theoretically use any can but the universal chinese cans wont have baffling inside to trap nearly as much oil.You would be looking to spend $100+ for a well made one from a known vendor like UPR or Elite.Additionally the ones intended for the 5.3 will come with a bracket intended for fitment on the Silverado so there is no need to fabricate one.The main difference installing on the 4.3 is the pcv ports will be in different locations from that of the 5.3 but its a bolt on deal for the most part

Doublebase · August 31, 2019

3 hours ago, WHITESSTOWPIG said:

Couldnt agree more.Also one could theoretically use any can but the universal chinese cans wont have baffling inside to trap nearly as much oil.You would be looking to spend $100+ for a well made one from a known vendor like UPR or Elite.Additionally the ones intended for the 5.3 will come with a bracket intended for fitment on the Silverado so there is no need to fabricate one.The main difference installing on the 4.3 is the pcv ports will be in different locations from that of the 5.3 but its a bolt on deal for the most part

I've actually had some good luck with a cheap Chinese can, plenty of baffling, does a nice job. These cheap brands - at least some of them - have done a nice job copying the better products. But yeah you won't get the bracket, you'll have to buy your own hose and clamps...not as nice as the expensive ones...not as big, no quick disconnects, etc. But they sure catch oil.

I wonder if the ports are easier to get to on the 4.3, with the port being in the rear instead of the front?

mookdoc6 · August 31, 2019

What? No clean side separator for those PULLS out of the grocery store? LOL

Side note: looks good!

WHITESSTOWPIG · August 31, 2019

14 hours ago, Doublebase said:

I've actually had some good luck with a cheap Chinese can, plenty of baffling, does a nice job. These cheap brands - at least some of them - have done a nice job copying the better products. But yeah you won't get the bracket, you'll have to buy your own hose and clamps...not as nice as the expensive ones...not as big, no quick disconnects, etc. But they sure catch oil.

I wonder if the ports are easier to get to on the 4.3, with the port being in the rear instead of the front?

Definitely easier and both ports are on the same side of the motor.I am thinking the intake manifold itself must have a check valve built into it because the line itself didnt when I cut it open to reuse the factory quick connects.If I had to do it again I would probably use a can from UPR.Its much cheaper and looked just as well built if not better than the Elite when I installed one on my other vehicle.

Doublebase · August 31, 2019

52 minutes ago, WHITESSTOWPIG said:

Definitely easier and both ports are on the same side of the motor.I am thinking the intake manifold itself must have a check valve built into it because the line itself didnt when I cut it open to reuse the factory quick connects.If I had to do it again I would probably use a can from UPR.Its much cheaper and looked just as well built if not better than the Elite when I installed one on my other vehicle.

I think the piece that the line attaches to at the manifold is an orifice. I believe it unscrews. At least it looks that way on the 5.3

Need More Coffee · September 10, 2020

A year old post and I made an account to ask this question.

On the 4.3 I see 2 lines that look like they could be vent lines. There is the one like the first/second photo. It is on the drivers side of the motor. There looks like a second one on the passenger side on the front of the motor. It runs from the valve cover to the intake box thing, not the air filter. Does anything need to be done with that line?

Grumpy Bear · September 10, 2020

No. The line on the passenger side is the fresh air inlet from the air box to the rocker cover.

There is a PCV valve at the back of the drivers side head with a hose that goes to the drivers side center of the inlet manifold. There is no orifice. The can is placed between the PCV valve and the manifold. Couldn't be more straight forward.

Need More Coffee · September 10, 2020

Roger that. Thank you.

Grumpy Bear · September 11, 2020

My turn for a question. Why are catch cans so small? I almost understand it in a baffled can but the ones without baffles need sufficient volume to lower space velocity enough to allow the separation of liquid from gas. Not sure a pop can sized volume would be enough.

Need More Coffee · September 12, 2020

From the photos I've seen they work decent enough. I would make sure it has some good baffling an even a bronze filter to help more vapor condense. I just got a cheap one from amazon that looks like a mishimoto but twice the size. Looks like 1.5 soda cans stacked. I'm also going to mount it next to the fender so it can have a little room from the engine heat.