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How to clean air intake


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I took the big black plate (not sure what it's called) off of the top of my engine today (2004 Hammerhead 380) and the metal plate underneath (intake manifold?) was very oily. I remember reading a thread recently where someone had posted a picture of theirs and told how they kept it clean, but now for the life of me I can't find it.

Does anyone else remember that? Can you help me out?

Thanks!

Jeff

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I wouldn't do anything, that's not bad at all. The PVC system is what causes that oil film and if you clean it now it's just going to get the same way. Any solvent's are just going to get into your cylinders and that could be worse.

Why did you take your injectors out?

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I took it off so I could get to the fuel injectors.

Like Tony said, why did you take the injectors out?

Does anyone have a recommendation for cleaning that?

Thanks!

I might wipe it down with some WD sprayed on a rag, you don't wanna put any harsh chemicals like carb. clean or brake clean on the paint.

If you have an excessive amount of oil, you might have a PCV problem. When's the last time you checked/cleaned/replaced the PCV valve? Some oil is normal.

I'd fix that hose clamp in the background of the picture that is near the T-stat housing. It doesn't look like it's on right unless you loosened it to move something out of the way.

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I'm trying to get to the bottom of a rough running/low power issue. I've narrowed the problem down to an issue with cylinders 5 & 7, and ruled out ignition/spark related problems, so now I'm looking at a problem with the fuel delivery. I took them out and went to NAPA to try to find a replacement. Unfortunately, they didn't have anything. I'm going to have to order some online next week.

As far as the hose clamp goes, if you're talking about the one right next to the intake, it's on there securely, it just looks funny. If you're talking about the two in the background, those hold the PerfectPass actuator and I had loosened them so I could move the cable enough to get the big black plate thing off.

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How did you narrow the problem down to those two cylinders? Cylinder power balance test? Compression test? Leak down test?

1 or 2 bad/low cylinders will give you more problems you would notice at idle like missing, chugging. (might answer your rough running if you're talking rough running at idle) You do know that the HH engine has a tall cam and the motor doesn't sound smooth to the untrained ear at idle, correct?

Low power in general is more of a broader issue. Is this something that came up recently?

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I just bought the boat a little over a month ago. I test-drove it before I bought it, but didn't really have anything to compare it to so I didn't know what to expect in the way of how much power it should have or how it should run. I did have them do a compression test before I bought it, and it showed 160 to 170 psi on all eight cylinders. It wasn't until I got it home and pulled some skiers that we noticed it had a hard time getting skiers out of the water. It also idles roughly and seems to take longer than it should to get a skier up to speed, particularly one that runs 34mph. I started working on it myself, doing the following routine maintenance items:

* Changed the oil and filter

* Replaced the impeller

* Replaced the fuel filter and checked the screen on the fuel pump

* Replaced the spark plugs and wires

* Replaced the distributor cap and rotor (being extremely careful to make sure that I reconnected the plug wires in the proper sequence)

One of the first things I did was to replace the spark plugs, and it seemed to run better after that. Then I did some of the other items on the list (namely replacing the distributor cap and rotor) and it went back to running poorly. I then had a mechanic check it out and he was the one that told me the problem was in cylinders 5 & 7. He arrived at this conclusion by removing the plug wires one at a time while the engine was running and noting how it affected the idle. He stated that there was no change when he removed the plug wire on cylinder 5, and that there was actually an increase when he did number 7. This guy was recommended to me as being an inboard specialist, but my interactions with him didn't give me a high degree of confidence, so I have an appointment to take it another guy on Monday evening. This guy (the new one) was the head mechanic at the local Malibu dealer until they went out of business earlier this year, and he comes highly recommended. I'm just trying to eliminate as many possibilities as I can before I take it to him.

Sorry for the long-winded post. Hope that explains the process that lead me to where I am right now.

Jeff

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I'm trying to get to the bottom of a rough running/low power issue. I've narrowed the problem down to an issue with cylinders 5 & 7, and ruled out ignition/spark related problems, so now I'm looking at a problem with the fuel delivery. I took them out and went to NAPA to try to find a replacement. Unfortunately, they didn't have anything. I'm going to have to order some online next week.

As far as the hose clamp goes, if you're talking about the one right next to the intake, it's on there securely, it just looks funny. If you're talking about the two in the background, those hold the PerfectPass actuator and I had loosened them so I could move the cable enough to get the big black plate thing off.

would it save a few $ and narrow the problem down to swap injectors from 5 & 7 into other cylinders?

i don't know, offhand, what the firing order is but if you suspect 5 & 7 injectors then putting those two next to each other in the firing order it may make the problem appear worse. or if 5 & 7 are next to each other in the firing order, split them so that they are not. should be able to tell the difference in sound, if not in operation. maybe? maybe not.

Edited by tvano
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One of the first things I did was to replace the spark plugs, and it seemed to run better after that. Then I did some of the other items on the list (namely replacing the distributor cap and rotor) and it went back to running poorly.

That seems suspicious. Are you sure you got the correct parts?

I then had a mechanic check it out and he was the one that told me the problem was in cylinders 5 & 7. He arrived at this conclusion by removing the plug wires one at a time while the engine was running and noting how it affected the idle.

Jeff

That is what I referred to as a cylinder balance test. Good, at least you got some good diagnostics.

would it save a few $ and narrow the problem down to swap injectors from 5 & 7 into other cylinders?

That would be a good idea since Jeff might still have all the injectors out. Then, he'd just have to realize how dangerous it is to pull a plug wire off a running engine. I don't think he's got the mechanical skills (no offense) to do this safely.

Jeff, when you had all the injectors out and at an auto parts store looking for replacements, did anyone ever ask you about having the injectors flow tested? This is what you could do real easily with them out if you can find a shop that can do it. Motorcycle shops do it a lot.

Edited by Pistol Pete
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Yes, I do realize how dangerous it is to pull a plug wire off of a running engine. That's why I didn't do that myself. I definitely know my limitations and stick to them. All of the parts I've used so far have either been the exact parts listed in the manual purchased from local parts stores, or parts purchased from Discount Inboard Marine on their recommendation.

At this point I think I'm just going to wait and see what Dr. J. (the former head mechanic at the Malibu dealership) comes up with. I've waited this long, a few more days aren't going to kill me.

I started this thread because I thought that the oily intake might be affecting the performance, but I was confusing that with a dirty throttle body so that's kind of a moot point right now.

Thanks for all the replies. At some point maybe I'll be the one answering the questions instead of asking all of the time!

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I'd like to hear the outcome.

I'm willing to bet that you're on the right track. Seems like you have a fuel delivery problem in those two cylinders.

But, the new cap and rotor making things bad again is an issue too.

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agree on the oil on the intake is coming from a clogged pcv system or bad pcv valve. change the pcv valve and check to make sure there or no clogs in the hose. you should not have oil on the intake and if the pcv system is working properly it will not get oily.

is it possible the intake gasket is leaking and causing the oil problem? also an intake gasket sucking air into #5 and 7 cylinders will cause a rough idle condition.

i would put all the injectors back in and change #5 and 7 injectors with a couple of other cylinders and if the problem moves to those cylinders then its the injectors.

pete is right about flow testing them but, switching them to other cylinders will tell you the same thing. i also think you should check the wires again. #5 and 7 fire in that order, you said it ran worse after the new cap and rotor so is it possible that those two got crossed. also looked at the pic and is that oil or just the usaul carbon that will build up in an engine?

for pete,

i've been building some high end race motors for years and have never had an issue pulling a plug wire to check cylinders.

i understand the shock you can get but, please enlighten me to the other dangers. gas fumes won't be an issue with the dog house open and well vented area.

curious on what the outcome is also.

Edited by sgt1970-442
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for pete,

i understand the shock you can get but, please enlighten me to the other dangers.

That's the only thing I'm talking about. I don't want this guy to get 50KV and bump his head on his engine cover.

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That's the only thing I'm talking about. I don't want this guy to get 50KV and bump his head on his engine cover.

ok now i get it...... :biggrin:

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That's the only thing I'm talking about. I don't want this guy to get 50KV and bump his head on his engine cover.

Been there and done that on my 1986 Chevy Cavalier when I was 16. Pulled a wire off the distributer while it was running, OUCH, hit my head on the hood, fell on my arse!!! Made me shaky and my whole body ached for a few hours :Doh:

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That's the only thing I'm talking about. I don't want this guy to get 50KV and bump his head on his engine cover.

That's why you use insulated pliers :biggrin:

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Been there and done that on my 1986 Chevy Cavalier when I was 16. Pulled a wire off the distributer while it was running, OUCH, hit my head on the hood, fell on my arse!!! Made me shaky and my whole body ached for a few hours :Doh:

only happens when you get your hand towards the end of the wire and you become the ground. we use to charge up condensors for points ignition and leave them on the work bench for someone to grab. talk about a zap.... :rofl:

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I don't care who gets zapped taking off a plug wire while an engine is running.

My main concern is the poor coil. You're really taxing the coil by not giving the spark a path to ground. :fingerwag:

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  • 3 weeks later...

If your engine is equipped with a horizontal style distributer cap(meaning wires attach to each side, not top), it is very possible to have a 5/7 misfire due to defective cap. If you look carefully at cap, you can see 5/7 run side by side. If you purchased a Echlin brand cap from Napa, its probably defective. Their Echlin caps for horizontal GM applications suck! I am a service tech and have more than 10 defective within a year or two. This style cap have a very high failure rate in automotive applications. I may be way off base here, but sounds probable to me. Faulty injectors are far less common than ignition related problems. Just cause a part is new doesn't mean it's good. Take a meter and check continuity between 5/7 on cap. If continuity exists, new cap is bad. Maybe this will help.

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Super excellent 2nd post Profast.

Thanks for the info. and welcome aboard. You'll have lots of opportunities to answer questions in your line of work here.

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