View Full Version : Any other 454 owners out there? (was backfiring)

09-02-2004, 02:05 PM
So I took my 1984 with a 454 into the dealer this week to have them look at my starting and running backwards issues (and to replace the leaky intake manifold gasket). As some background, from my post on the old board I've had the boat run backwards on me 2x in the past 4 years and hydrolock by sucking water in through the exhuast. It also starts somewhat slowly.

The timing, compression and starter all check out. I replaced the ignition switch and cleaned all the connections. The dealer could only suggest putting in a new battery and I'll see how that does this weekend. He says it starts and runs great.

But in talking to him he says that the 454's are known for running backward because of the high compression. He says they work for a while and as he put it, "then go boom." :uglyhamme He says you can't do much about it, but keep the boat in tune (which mine was). The other dealer I deal with really didn't have any clues as to why this would happen. SkiDIM and folks on this board suggested the ignition switch and timing.

Since everything has checked out, I'm curious if this has happened to anyone else and if anyone has experiences with the 454s? :confused:


lakes Rick
09-02-2004, 07:08 PM
As a kid ( a long time ago) the only way we could prevent some of the cars we had from running backwards, was keeping them in gear when we turned them off.. Put it in gear before turning off key..

Is your idle too high?? Or possibly installing a fast idle solenoid would be of help........

09-02-2004, 08:00 PM
Your freaking me out! :eek: now I have something else to worry about!!!...never heard of that one....Scott what prop are you running and what your top speed and rpm...(in forward :D )

09-02-2004, 08:20 PM
Scott ...I added another solenoid it helped my starts....I bought it from Mallory...if your interested I can get you the info...I used to get it rebuilt every year....havent for 2 and it goes vroom!

09-02-2004, 11:42 PM
It doesn't diesel when shutting it off, only when starting and it happens before the engine ever catches. It's like it gets to the top of a compression stroke and then doesn't have enough momentum to continue on and goes backwards... just for a nanosecond, but long enough to suck water into a couple of the cylinders.

The idle if I recall correctly is about 700 or so in neutral and drops to about 550-600 in gear which seems about right to me. What would a fast idle solenoid do?

Scott88, did you replace your solenoid (and I'm assuming you're talking about the starter solenoid) or add a second one in addition to the first? The solenoid on this boat is integrated with the starter from what I can tell.

As for prop I'm running a 13x13 OJ Legend and top speed at WOT is about 45-46 mph at about 4600 rpm. The boat runs great all the time once started: idles well, great holeshot, smooth cruise, and good top end. I'll see how the new battery and cable ends do this weekend to help with the slow starting. THe old battery was at least 5 years old. It checked out fine on the bench tests earlier this summer, but who knows?

I'm assuming that the slow starting is most of my running backwards problem, but who knows? No one seems to have any definite ideas and everything I check seems to be set correctly.

09-03-2004, 02:28 AM
My 351W Ford engine did the same thing last summer. In my case it seemed like the spark was not quite strong enough to start the engine until you let off on the key and then it kicked backward (probably slightly before TDC on a cylinder) It happened once this summer, as well, but this time it did not suck water into the cylinders. I've replaced everything in the ignition system,timed the engine, and installed a new battery but I'm still nervous when I turn the key. I'll be following this thread for any advice.

09-03-2004, 07:48 AM
Hey Scott,

Mine hasn't run backwards yet...I've owned the boat for about 2 months. I had some issues with the starter/solenoid and alternator which I've had rebuilt and that part of the problem seems to have been resolved.

I just installed a Pertronix electronic ignition system the other evening and she fired right up after the install - ran smoothly, it was great...However, yesterday I went to start the boat and had to crank on it for a while to get 'er to start but it DID start. (similar symptoms to pre-Pertronix install) Then, after running for about 45 mins I started to get a miss - sporatic but still a miss...I've not had time to check this out yet - but I guess that's a question - what to check first? I 've installed new plugs and wires but re-used the existing cap and rotor.

I DID NOT re-time the motor after the Pertronix install, in fact, I'm embarrassed to admit I've forgotten how to time a motor so there's another question and then what is the timing info for a 454? I assume if a buy a timing light, the directions will show me where to connect the leads...I just can't remember as it's been since the early '70s that I've fooled with motors at all.

Sorry to highjack your thread, Scott....


09-03-2004, 09:49 AM

Thanks for the rpm stats!


This is the additional remote starter solenoid that I installed. It was explained to me that because of the distance from the battery to the starter it causes over heating the existing starter solenoid. It solved my starter problems and it was cheap.

In my previous post I said it was from Mallory...its not ....its from Mr. Gasket

HOWEVER I COULD BE WRONG!!...I differ to the omnipotent all knowing guys like Jimn.

09-03-2004, 02:44 PM

Sounds like you have the exact same issue I do... and sounds like you have done most of the same things I have. The folks at Discount Inboard Marine only suggestion was that the ignition switch might be worn out and not giving enough juice to the coil when in the start position. For $18 and 10 minutes to install I figured it was something to replace as well. I'll see how the boat goes this weekend.


Call up SkiDIM and have them send you the manual for your engine. They have all some pretty good ones. Timing on the 454s seem to all be at 10 degrees BTDC. Your timing light will tell you how to hook it up and then you just simply get the engine to 1000 rpms and line up the line on the crankshaft pully with the appropriate marking on the overhanging mark (sort of jagged thing). As for starting I find that this motor takes LOTS of gas to get going. I give it a good 4 or 5 pumps of the throttle and it can take a good 3-5 seconds (which seems like forever) before it catches. I think it's just a factor of the big block being a gas hog. As for the miss, hopefully someone with more experience will chime in, though I would check/replace your fuel filter as a good place to start. Then seem to get clogged pretty quick. I was told to replace it every year.

09-06-2004, 11:32 PM
So I have some good news to report. After I replaced the ignition switch the dealer replaced my battery and the battery end of my cables. The boat now cranks properly and fires a lot more quickly than before which is much more reassuring! I had the battery tested twice this summer and it checked out fine both times, but getting a new one seems to be a large part of the trick I guess.

The boat still doesn't always catch the first time though. It always catches the second try. So I guess I still have a bit of work to do. I do get a bit of blue and sometimes brownish smoke out the back just after it starts so I'm guessing I have some leaky lifter seals since the compression checked out good at 150 on cylinders 1-7 and 145 on cylinder 8. That might explain the blue smoke, but the brownish smoke I'm unsure about? I also noticed that in the AM after the boat sat in the water all night I left a tiny gas slick on the water after starting it up. So now I'm wondering if the boat if running rich maybe? Other than it not catching quite as quickly as I'd like it sure runs nice. Idle seems a tad high (correction to my last post). 800 in neutral and about 650-700 in gear.

Any thoughts on what to look at next? I'm guessing carburator is the next logical step, but I'm clueless about adjusting them... Unless someone tells me that replacing the lifter seals is easy I figure that I'll just let them leak for a while until the problem gets worse.

09-07-2004, 09:14 PM
Hey Scott,

I've some good news as well...the miss seemed to go away after I took the distributer cap off, removed the Pertronix magnet thing, cleaned the cap and rotor and reassembled.....now I noticed another thing - hard to explain without photo but I'll give it a go - over near the choke there's a piece of plastic that appears to be part of the lever-arm that operates the choke when the throttle is placed wide open - rhis has broken....I need to go see what dual pumper carb. I have, but I assume this may have something to do with my hard-starting issues as I also need to "pump" my throttle several times and if my recall is correct, this lever arm used to hold the choke plate in the choke position? but now obviously does not....hey it's a boat I tell my wife, things are supposed to break....

Oh yeah, thanx for the timing info....


Jeff N.
09-08-2004, 12:55 AM
Scott -

My 82 w/ the 351 greatly benefited from a professional carb rebuild. I had done it myself several times but the pro rebuild really helped. Starts better, idles WAY better and throttle response is nicer as well.

Maybe something to factor in as you work your issues.

Also, I'm a pretty big believer in an upgraded ignition with slightly opened up plug gaps for these era engines. You can upgrade the stock coil via a Jacobs or similar unit. Or, go for the whole tamale and add in a full electronic ignition. I have a Jacobs unit in a box via ebay ready to go into my boat. Did WONDERS for my old 390 72 F250 and expect similar improvements on the PCM 351...


09-13-2004, 12:37 PM
Sometimes this engine baffles me... It seems that everytime things point to a carb rebuild (popping on acceleration, not starting cleanly) the problems clears itself up. Not that I mind.

We had absolutely beautiful weather this weekend, 75 degrees, no wind, low humidity and the lake was pretty close to empty. The boat ran great. It started right up with just a bump of the starter, just as one would want. Still smokes a bit on startup, but I figure that's what I get with a 20 year old motor. I'm just happy it starts and runs great!

09-14-2004, 05:52 AM
Don't worry about the smoke at startup. I have a buddy who had his whole engine "freshened up" (bored, new bearings, etc)... and replaced his carb with EFI. Why - I don't know.... Anyway Each time he starts up - it leaves such a large cloud of blue smoke you can't see anything behind the boat. He's wishing he would have left it alone. :rolleyes: