Ticking noise on 454 mag

[tcgravy]

Re: Ticking noise on 454 mag

what is your fuel pressure?

carbs have issues over 4psi

Need to check that, will try to do it tonight. Also, these pumps say they have an "internal pressure regulator" in them - I'm thinking there is a possibility this failed, causing my ultimate demise. I guess the pressure test will agree or disagree with this.

I know that I have a carter electric fuel pump on it, part # says 152-875 (which I think is the same as P4389 pump). This came on the boat when I bought it 3 yrs ago and has never been a problem. This part # / fuel pump says its rated at 6 psi max.....can't find any other replacements at less than 6 psi max?

Is there a possible replacement that would be more like 3-4 psi max? I have found multiple "marine" electric fuel pumps, all of which seem to be rated at 6 psi max.

 

[Scott Danforth]

Re: Ticking noise on 454 mag

or a pressure regulator.

I used to run a Holley FPR with every electric fuel pump. not sure if its marine rated.

I did find the both the Holley 12-803 (4.5-9psi) and the 12-804 (1-4psi) on a marine website.

 

[tcgravy]

Re: Ticking noise on 454 mag

what is your fuel pressure?

carbs have issues over 4psi

Checked fuel pressure (after the pump)......10 psi & rising....whoops. Looks like these little Carter electric fuel pumps have an internal pressure regulator that failed, so the pump worked fine it just never regulated the pressure. Replaced with new pump of same model, tested fuel pressure (after the pump) and only 2 psi (which may be too low, but we're only measuring at idle here and this would be another story so we'll see after the first lake test).

Anyways, after install the needle & seat is working fine again and no more gas flowing out the top of the carburetor, no more cylinders full of gas and hydrolocking.

Also, FYI for any future readers of this post, it appears that Carter / Airtex fuel pumps 4070, 4389, e84389, and 152 875 are all identical. I purchased a "4389" from Auto Zone for $85 that also has p/n 4070 stamped on it, a sticker that says 152 875, and the box said e84389.

Thanks for all the help thus far, time to re-set the valve lash to spec again and will post with another update once all problems are gone....

 

[Scott Danforth]

Re: Ticking noise on 454 mag

2psi is fine for stock needle and seat.

glad you found the problem.

 

[tcgravy]

Re: Ticking noise on 454 mag

you may have had collapsed lifters and now the valves are hung open since you adjusted them. I would have adjusted them running, however that is me.

OK BACK TO THE VALVETRAIN......

Re-adjusted lifters (engine not running) per spec/procedure of Mercruiser service manual. Problem is that after tightening down rocker nuts to spec it appears I have 2 valves where the nut is down significantly more than the others, more threads showing (intake #4 & exhaust #6). Everything else looks good and consistent on all other valves.

The other thing about these 2 valves is that when I find "zero lash" and then tighten them an additional 3/4 turn, they are VERY HARD to turn. Am I looking at a couple of collapsed lifters? Should I run the engine a while hoping they "free up?" Also, if I do that, where should I set the rocker nut? Tight? Loose? At zero lash? Just dont want to have them too tight and have a valve + piston contact.

Engine will start very easily (although I've only started it, not run it at length). Oil level is where it should be. Other thoughts?

 

[tpenfield]

Re: Ticking noise on 454 mag

I'd go ahead and replace those couple of lifters . . . unless you see an issue with those rocker arms that would explain the difference in the depth of tightening on the studs.

 

[tcgravy]

Re: Ticking noise on 454 mag

I'd go ahead and replace those couple of lifters . . . unless you see an issue with those rocker arms that would explain the difference in the depth of tightening on the studs.

I inspected rocker arms & push rods as well as the rocker arm studs (to make sure they arent backing out), all of which seem fine, which does point to a problem w/ the lifter. Also no metallic visuals in the oil (possibly indicating bad came lobe, so cam seems fine) If I replaced the 2 lifters I would likely replace all lifters on both sides at once.

I am just wondering the following before I take the intake off to replace the lifters:

1) if it is possible that the stuck lifters will "free up" after running a bit, as I have read about that elsewhere. Either just from running or putting in thinner oil to help free the sticky lifter.

2) if it is possible to adjust these 2 stuck lifters as if they were solid lifters? That is to say, to adjust them to exactly "zero lash" knowing that the normal preload of the lifter wont be working.

3) if running it like this is going to hurt anything?

Let me know.

 

[Scott Danforth]

Re: Ticking noise on 454 mag

I inspected rocker arms & push rods as well as the rocker arm studs (to make sure they arent backing out), all of which seem fine, which does point to a problem w/ the lifter. Also no metallic visuals in the oil (possibly indicating bad came lobe, so cam seems fine) If I replaced the 2 lifters I would likely replace all lifters on both sides at once.

I am just wondering the following before I take the intake off to replace the lifters:

1) if it is possible that the stuck lifters will "free up" after running a bit, as I have read about that elsewhere. Either just from running or putting in thinner oil to help free the sticky lifter.

2) if it is possible to adjust these 2 stuck lifters as if they were solid lifters? That is to say, to adjust them to exactly "zero lash" knowing that the normal preload of the lifter wont be working.

3) if running it like this is going to hurt anything?

Let me know.

1.) you can put a bit of kerosene or diesel in the oil as a solvent. dont run it more than a minute or two at idle. then change oil.

2.) not a good idea.

3.) if they come "unstuck" you can hang a valve and burn it.

lifters are dirt cheap. However at that point if was me, and I was replacing lifters I would do a complete cam and lifter set along with a new timing chain.

 

[tcgravy]

Re: Ticking noise on 454 mag

LIFTERS REPLACED - NEW UPDATE

After replacing lifters, running on muffs for a while, checking and re-checking valve lash, etc.....took it out to the lake for a real test. Let it warm up at idle for a while, then cruised for about 10 min until it got up to temp (about 160 degrees), everything seemed to be running great with no problems whatsoever....

then went to WOT, wouldnt pull rpms (should pull 4600-4800, only pulling 4000-4200).....after about 30 seconds of running it hard/WOT, backed off the throttle back to cruising (about 3000 rpm), engine made some clanking noises (like a small hammer hitting something, inconsistent, not ticking, only happened 2-3 times), right when I heard noises I pulled throttle back to idle and saw that oil pressure gauge said 0. WHOOPS. Pretty sure the oil pressure gauge is accurate because w/ oil pressure down it was ticking and chattering like crazy even at idle so I shut it down very quickly........Also found a little bit of oil sitting on top of the intake manifold around the carb (but not much), no idea how oil can get on top of the intake??? Checked the oil with the dipstick, level seemed to be fine, right between "add line" and "full line" and there was no sign of water intrusion.

Started boat up again 20 minutes later and it had oil pressure again while idling, ticking was gone too. On this startup, oil pressure started at about 5 psi then slowly climbed up to 35 psi. Let boat cool off for an hour, then tried again....exact same thing happened (warmed up for about 10 minutes, oil pressure and everything else was fine, then started making noises, then lost oil pressure).

This is so fun....Debris in the oil? Bent a couple of pushrods? Time for new lifters all around?

 

[Scott Danforth]

Re: Ticking noise on 454 mag

I would be pulling the motor at this point. get it on a stand and start inspecting.

Melling oil pumps for SBC and BBC's are cheap (about $40 for a high pressure unit). I would put one in.

oil on top of the intake would be a leak, probably from where the oil pressure gauge is, or from the breather tubes.