92 351 has major knock
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=40984
Printed Date: April-29-2024 at 10:09am
Topic: 92 351 has major knock
Posted By: ibiz
Subject: 92 351 has major knock
Date Posted: April-30-2017 at 10:51pm
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When I took my 92 SNOB 351 out of storage last week it had a loud knock/tick coming from the driver's side of the engine. The boat shop looked at it and then I took it to an old time mechanic shop that knows engines. In 2014 I had the original block replaced with a Jasper block due to a crack in the block. 3 seasons and 110 hours later now I have a really bad knock. The machine shop repair place upon my approval took a chance and I had all the lifters replaced. It didn't resolve the knock. Short of pulling the motor and dropping the pan it appears that we will end up running it this Summer until it dies. The oil pressure is great 60+ lbs and the compression is good all around except for the #2 cylinder which is a littler lower but not a big issue. The boat is stored in the underground caves here in KC where it doesn't get below 60 degrees all winter. It's got me totally baffled as to the cause, the knock wasn't there at the end of the season when we put it on the trailer. The boat shop is suggesting I just replace the whole motor with a new PCM crate motor - 5.7l with EFI etc. Any suggestions? Anyone know about someone who has put a new GM/PCM engine in a 92 Nautique OB? |
Replies:
Posted By: Shep72
Date Posted: April-30-2017 at 11:16pm
| Pull the valve covers and press on all the rocker arms. Could be a stuck lifter or you might have a collapsed lifter. If it is collapsed you could have a wiped lobe. Best case, new cam solves it. Depends if it's a tapping or a knock. But if it ran good last year don't think it would start knocking from sitting over the winter. |
Posted By: Gary S
Date Posted: April-30-2017 at 11:21pm
------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1711&sort=&pagenum=1&yrstart=1966&yrend=1970" rel="nofollow - 69 Mustang HM SS 95 Nautique Super Sport |
ibiz wrote:Posted By: Duane in Indy
Date Posted: May-01-2017 at 7:36am
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Since it had no problems when you put it in storage and now it has, leads me to believe that there is an outside chance that carbon has broke loose in one or more cylinders. Run engine at very fast idle and trickle water down the carb. If it is carbon it may steam itself out. Beats taking it apart. Have seen that fix done before. Duane |
Posted By: KENO
Date Posted: May-01-2017 at 7:48am
Having no idea what your knock/tick sounds like, I'll ask the silly question, is there any chance it's external to the engine? A loud knock and a tick wouldn't exactly sound alike. A short video would be real helpful to people. Your raw water pump is on the right side and if it has a bad bearing you can get some funny noises from that. You could remove the belt and start the engine long enough to see if the sound is still there. Could be a long shot but won't take long to find out if it's the pump |
Posted By: ibiz
Date Posted: May-01-2017 at 11:09am
| Several knowledgeable people besides myself have listened to the engine. It's not the raw water pump. Thanks for the suggestions, I am open to any ideas at this point in time. |
Posted By: ibiz
Date Posted: May-01-2017 at 11:10am
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Duane, Thanks for the suggestion. I will likely give that a try. |
Posted By: KENO
Date Posted: May-01-2017 at 12:25pm
Video |
Posted By: 8122pbrainard
Date Posted: May-01-2017 at 2:09pm
| Have you checked for cracks or leaks where your exhaust manifolds bolt to the block? They can produce a sound just like a lifter tick/knock. |
Posted By: Shep72
Date Posted: May-01-2017 at 2:19pm
| What's your idle speed. Flex plate in trans rattling? Does the noise increase or go away with higher rpms? Can you stick your ear to a long screwdriver and narrow down where the noise is coming from? |
Posted By: SNobsessed
Date Posted: May-01-2017 at 2:41pm
| Pouring some marvel mystery oil down running carb can knock carbon loose too. |
Posted By: 75 Tique
Date Posted: May-01-2017 at 6:33pm
Yeah, find a new shop. You need a new engine is a pretty drastic "parts swapping" for a tick. I think there are other things to check before dropping in a new motor. |
Posted By: tryathlete
Date Posted: May-01-2017 at 6:48pm
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Ibiz we need a video with you moving around the engine. stuck or collapsed hydraulic lifter sounds rational. Did u run it on the hose before taking it out this season? Remote chance you turned off the engine before shutting off the fake a lake? Could possibly have hydrolocked a cylinder and bent a connecting rod. Maybe drop pan (ugh) and look for main or rod bearing material. I'm sorry I'm. It much help without audio. You can learn a lot from Sound (where from, 1/2 crank speed or crank speed). Get us all a video so we can guessculate. |
Posted By: 8122pbrainard
Date Posted: May-01-2017 at 7:14pm
I agree with Larry that you do not need a new engine but rather a new shop/mechanic. |
Posted By: MrMcD
Date Posted: May-01-2017 at 8:07pm
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With your engine running ( and Knocking ) remove one spark plug wire at a time on the noisy bank. If this makes no change in your noise it is in the overhead, Cam, Lifters and valves. If the noise gets quieter with the guilty plug wire pulled off you can isolate to that cylinder. It will be related to the Piston, Connecting rod or Main bearing under that cylinder. Carbon deposits can make a piston rock hard in a cylinder and create a sound similar to a lifter tap. A rod knock is lower in the block and louder, same for a main bearing. I have heard of Fuel Pumps causing loud knocks when they go out also so rule that out. For $15.00 you can buy a mechanics stethoscope at the local parts store and isolate your noise location. If water got in that cylinder it could bend a rod and cause the piston to make noise. Jasper Engines is a very reputable house. You can call them tell them all details and they will help diagnose also. They may even stand behind the engine or at least partially stand behind it since it is most likely out of warranty. They do good work and use good parts so you chose a good engine. |
Posted By: ibiz
Date Posted: May-02-2017 at 7:04pm
| Yes I have. |
Posted By: ibiz
Date Posted: May-02-2017 at 7:06pm
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I will take a look at the troubleshooting tips you suggested. But both the Boat shop that bought the engine from Jasper and installed it and the automotive shop that does a lot of work with Jasper got no where with the Marine rep. They were told it's a two year warranty period! They wouldn't budge and provider any reimbursement for parts or labor. |
Posted By: ibiz
Date Posted: May-02-2017 at 7:11pm
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I will get a video/audio of the noise and post it here. Unfortunately, due to business travel it's going to be another week before I can post back here. The engine was run on the trailer to pull in 3 gallons of anti freeze at the end of the season. Engine was shut off as soon as it got to the bottom of the antifreeze in the bucket. absolutely no knocking at that time when it was run on the trailer.. |
Posted By: 8122pbrainard
Date Posted: May-02-2017 at 7:36pm
Did you drain ALL the water out of the system first? ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: KENO
Date Posted: May-02-2017 at 7:50pm
I hardly think it matters in the grand scheme of things considering the above |
Posted By: ibiz
Date Posted: May-02-2017 at 7:52pm
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Yes. all the water was drained out of the engine first and then it was run with the antifreeze. But also note here in Kansas we have underground caves in the area so it was stored in a constant 65 degree environment all winter - no chance of freezing. |
Posted By: ibiz
Date Posted: May-07-2017 at 12:59am
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Okay guys, I have created two videos and uploaded them to onedrive for anyone that wants to listen. There is one with the engine cover up and it's recording the knock from a cold start. The other is with the cover down after the engine is warmed up. https://1drv.ms/v/s!AqJGILMQ7vgygeAzZjsMNGzQocsgUQ Your thoughts Jerry |
Posted By: Smithfamily
Date Posted: May-07-2017 at 9:15am
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Sorry you are having problems Jerry! While I am no expert, and you got some excellent advice here, I will say that I have spun a few bearings before and that noise does NOT sound like a knock/noise from that. Not as loud or consistent. Good luck with it. Please keep us posted. ------------- Js |
Posted By: 8122pbrainard
Date Posted: May-07-2017 at 9:22am
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https://1drv.ms/v/s!AqJGILMQ7vgygeAzZjsMNGzQocsgUQ" rel="nofollow - Here's a direct link to Jerry's video Jerry, Did you?
------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: ibiz
Date Posted: May-07-2017 at 10:52am
| Yes we have checked for leaks. |
Posted By: Shep72
Date Posted: May-07-2017 at 1:15pm
| I never found the cold start video. Did you pull one plug wire at a time to find out if it was specific to one cylinder? |
Posted By: KENO
Date Posted: May-07-2017 at 5:29pm
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Jerry Here's a video from last year in the linked thread just for reference  You can compare noiseshttp://www.correctcraftfan.com/forum/forum_posts.asp?TID=39011" rel="nofollow - ticking noise Edit seem to have to click a couple of times on the start symbol to get sound. |
Posted By: Duane in Indy
Date Posted: May-07-2017 at 5:43pm
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When you shot the videos, how did the water/steam trick do???? ------------- Keep it as original as YOU want it 1978 Mustang (modified) |
Posted By: ibiz
Date Posted: May-07-2017 at 11:31pm
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I didn't try the water/steam trick yet. I wanted to upload the video/audio and get more feedback before I tried that. Do you think the water/steam approach is the same as pouring some marvel mystery oil down the carbs? It seems to be similar from what i have read online? |
Posted By: ibiz
Date Posted: May-07-2017 at 11:32pm
| I am going to go out next weekend and try some of the suggestions. There are no leaks where the exhaust manifold connects to the blocks. |
Posted By: MrMcD
Date Posted: May-08-2017 at 5:06am
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Has the engine been overheated? Almost sounds like piston scuff or a loose lifter/rocker arm. ------------- |
Posted By: ibiz
Date Posted: May-08-2017 at 9:32am
| no it hasn't been overheated. |
Posted By: ibiz
Date Posted: May-17-2017 at 4:27pm
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Update. 1. Tried Marvel Mystery Oil in the carb - no change. 2. Tried MMO in gas tank - no change 3. Tried MMO added to oil - no change yet but wasn't able to put in 20% 4. Tried removing one sparkplug wire at a time. No change in knock. Jasper won't cover it, its out of warranty. :) |
Posted By: tryathlete
Date Posted: May-17-2017 at 5:41pm
| Sounds like a collapsed lifter to me. Pull the valve covers just to take a peek while it's running. If so it's a quick fix. |
Posted By: ibiz
Date Posted: May-17-2017 at 6:01pm
| The lifters have already been replaced. |
Posted By: tryathlete
Date Posted: May-17-2017 at 6:53pm
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We're the lifters replaced since the noise erupted? Any contaminants (like carbon or dirt or metal chips) that wind up in the oil can wind up in a lifter and can block oil flow into a hydraulic lifter stopping it from expanding to zero the gap at the rocker. From my earbuds the tick sounds like a lifter or exhaust leak and you've said there's no exhaust leaking. One little thought is that the distributor rotor might be striking the inside of the cap if it's not locked down properly. |
Posted By: ibiz
Date Posted: May-17-2017 at 7:04pm
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the lifters were replaced after the noise started. The oil was drained, flushed, lifters replaced and then new oil was put in. I will double check for exhaust leaking and the rotor. FYI to all. My skiing buddy that was with me when ran the boat the last day of the season and then ran it on the trailer to suck in the antifreeze agrees with me. The noise was not there last season. This is something that some how happened between when it got turned off in October and when it was started up in May. |
Posted By: throttle out
Date Posted: May-18-2017 at 10:05am
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It certainly sounds like valve-train or exhaust leak. My old silverado sounded identical to that when cold noise would be gone in 2 minutes, manifold gaskets took care of it. I know you cant find an exhaust leak so we will rule it out for now. I did an ls swap on my 87 chevy shortbed 4x4. It is an LS1 out of a donor car. I drove the car before buying and the engine ran great. It however sat for sometime before I could perform the swap and the oil was like sludge when I changed it before fire up. The engine sounded awesome but after about 200 miles it would randomly start a nasty lifter knock, sounded just like your boat does. I did some quick oil changes and got the crud out, but more to the point, pull your valve covers and have a look !!! Could be a loose rocker arm, slightly wrenched push-rod you wont know until you look. Maybe upon first fireup this year it backfired? I've seen a good back fire tweak a push-rod. Good luck!! ------------- 1989 Ski Nautique 2001 351 PCM w/ 1-1.23 |
Posted By: KENO
Date Posted: May-19-2017 at 8:36am
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It sounds like you haven't found your tick yet, so if you've ruled out everything that's been mentioned maybe it's time to think about the cam itself having a bad lobe unless your mechanic verified the lobe lift or valve lift to be the same on all 16 lobes/valves. Did he verify that all the pushrods were straight and all the rocker arms good? Shep 72 hinted at this early on along with throttle out A cam lobe going bad usually starts as a tick.from the valve train as clearances open up (and gets progressively worse) What kind of oil are you using and how was the new engine/cam broken in initially? Not telling you it's your problem but giving you things to think about as possibilities since you're stumped right now. |
Posted By: scootdogydog
Date Posted: May-19-2017 at 11:49am
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How do you know there are no leaks? based on the noise, as others are suggesting, it sounds like a lifter/exhaust noise. I'd recommend buying a stethoscope and move that around while you can hear the tick. This would help identify where the tick is coming from...and lead you in the right direction ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=7183" rel="nofollow - 1999 Python 1980 Ski Tique 1968 Mustang WIP |
Posted By: KENO
Date Posted: May-19-2017 at 12:23pm
The stethoscope came up 18 days ago, he's done the plug wire routine with no noise change |
Posted By: scootdogydog
Date Posted: May-19-2017 at 12:27pm
The idea came up...I missed that. Did I also miss the result? If not, hopefully they get posted soon ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=7183" rel="nofollow - 1999 Python 1980 Ski Tique 1968 Mustang WIP |
Posted By: ibiz
Date Posted: May-19-2017 at 12:40pm
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I haven't done the stethoscope yet. will do it this weekend. The local auto parts store was out of them. FYI, the exhaust risers have been on and off as part of the replacement of the risers as on the 351 ford you can't get to a bolt for the valve covers without removing the risers. So there has been some 'repair' of the risers gasket seating during the troubleshooting process. |
Posted By: Shep72
Date Posted: May-19-2017 at 12:52pm
| On my 94' I removed my Valve covers with a 1/4" drive ratchet long extension and universal joint over the socket.. This may help if you tear back into the Valve covers. |
Posted By: 81nautique
Date Posted: May-19-2017 at 1:12pm
they're not talking about the riser gaskets, they're talking about the manifold to head gasket. when they leak there it can sound like a knock. |
Posted By: KENO
Date Posted: May-19-2017 at 1:58pm
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I'm thinking he means the manifold to head gaskets and that his mechanic took the manifolds off way back when, so he could get to the valve cover center bolts so they could do the lifter replacement. Not everybody does the 1/4 inch ratchet/extension/universal joint routine.as it's still a bit of a PITA. If that's the case he had the noise before and after the manifold gaskets were replaced. Just me thinkin'. |
Posted By: MrMcD
Date Posted: May-21-2017 at 3:42pm
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Years ago I had a little coolant get into one cylinder, Head gasket was failing and I did not know it. It dripped enough on that cylinder to form a slight Hydro Lock, The engine started just fine but knocked like a loud lifter tap. Turned out the hydro lock had bent the connecting rod just slightly, enough to make one side of the piston touch the head on every rotation. Engine ran just fine but had that noise. I ran it a couple months and it never got louder and never got better. This boat had 1,200 hours on it so I planned to do the heads, it was starting to foul spark plugs. On tear down I could see the spot on the head and on the piston where they had been touching slightly. New heads, one new rod and it ran like a top till I sold it 300 hours later. In a boat with a constant supply of fresh cooling water a leaking head gasket can go undetected at first. ------------- |
Posted By: Smithfamily
Date Posted: May-22-2017 at 7:13am
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Whats the post weekend update Jerry? Hope its good news? ------------- Js |
Posted By: KENO
Date Posted: June-21-2017 at 12:09pm
| It's been about a month.................wonder if it's still tickin? |
Posted By: ibiz
Date Posted: June-21-2017 at 1:56pm
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It is still ticking, although a little more noticeable than before. We have about 4 hours of skiing and running on it. I plan on changing the oil in 5 hours to see what it looks like - ie any signs of metallic in it. The plan/hope now is to hope it holds out for this summer, then pull the engine over the winter, do a repair and re install. Thanks for checking in. |
Posted By: KENO
Date Posted: June-21-2017 at 2:23pm
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Glad you're skiing and having some fun with it. Hope you get thru the season OK What oil are you using now? Whatever you give for an answer will probably start another oil discussion but that's OK
|
Posted By: ibiz
Date Posted: June-21-2017 at 2:27pm
| valvoline 20w - 50 racing oil |
Posted By: Bri892001
Date Posted: June-21-2017 at 2:37pm
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Before you do any kind of major repair or engine pull, definitely rule out your exhaust manifolds and exhaust manifold gaskets. I had a similar tick for a while and my brother and I fixed it two weekends ago. When I first saw the old gasket, it looked like it was in pretty ok shape to me. I didn't have high hopes that replacing the gasket would fix it, but sure enough it did. My brother also cleaned up the mating surfaces really well, using a flat file on the manifold and brash brush and gasket scraper on the head. These are pics of the gasket, if you look close you can see where it was blown thru just a little. My boat only made the noise under load (in gear) and I could never feel the leak externally, which was weird.  
|
Posted By: KENO
Date Posted: June-21-2017 at 2:44pm
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Ok no oil discussions needed maybe I should capitalize that, NO OIL DISCUSSIONS NEEDED Bri they've been thru the gasket issue already |
Posted By: Bri892001
Date Posted: June-21-2017 at 3:14pm
Well, the riser gaskets... but a tick is more likely to come from the manifold (to head) gasket. |
Posted By: fgroce
Date Posted: June-21-2017 at 3:26pm
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Since you still have the tic and are set on running the boat, I would order an oil testing kit for oaitest.com. The company name is Oil Analyzers Inc. you can send then in oil sample and they will tell you if any particulates are in your oil. If the oil test is good keep running the engine for the summer and try the gaskets on the exhaust manifolds. Maybe this added information will keep any terminal damage from being done. Good luck. ------------- FGroce 88 Ski Nautique For 28 years Now 2002 Ski Nautique |
Posted By: ibiz
Date Posted: June-21-2017 at 3:37pm
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Just to recap also regarding the gasket leak theory vs internal engine issue. I don't think there is any doubt that its an issue internal to the engine. I have had some qualified mechanics look at it and we have verified it. However, if it is just a leaking gasket then I presume that there is no error damage occurring and it will run 'forever'. |
Posted By: fgroce
Date Posted: June-21-2017 at 3:43pm
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If gaskets fix it an the sound goes away, Good to go. I would just hate to sling a rod and ruin a repairable engine by running it till failure. ------------- FGroce 88 Ski Nautique For 28 years Now 2002 Ski Nautique |
Posted By: KENO
Date Posted: June-21-2017 at 4:04pm
Since taking a riser off the manifold really does nothing for your ability to get the valve covers off, I figure what Jerry meant here was that the manifolds had been off the heads and put back on. I think he's calling the whole assembly a riser I guess Jerry can verify whether it's had new manifold to head gaskets on it. |