1989 Mercruiser 4.3

[Fiveo Invader]

Re: 1989 Mercruiser 4.3

A seperator; couldnt tell you. The gas smells fine and sloshes around so I dont think its gelled up. I know that gas will go bad after like a stagnant year. I drained the fuel this morning only like 3 gallons in there which was a relief. My brothers coming by tomorrow evening and we will do the tune.

This is a stupid question, iknow, but how do i get the oil out. theres a drain plug but i cant imagine thats the way out. i can barely get to it and with a full drain pan its not comin out of the hole. Whats the trick?

 

[180shabah]

Re: 1989 Mercruiser 4.3

On marine engines the dipstick goes all the way to the bottom of the pan so you can suck the oil out from the top.

 

[Bondo]

Re: 1989 Mercruiser 4.3

On marine engines the dipstick goes all the way to the bottom of the pan so you can suck the oil out from the top.

Ayuh,......

Not that it'll help you this time,...
But,...
There's a Kit that replaces the drain plug in the pan that has a Hose attached,+ can be pushed out the bilge drain to empty the oil....

 

[Coors]

Re: 1989 Mercruiser 4.3

One cylinder fouling could just be a wire; Not the carb.

 

[Don S]

Re: 1989 Mercruiser 4.3

Hose attached,+ can be pushed out the bilge drain to empty the oil....

Those are more usless than a stringer drive powered by a 470!
HOT oil only dribbles out at best and normally takes overnight in warm weather.
Warm the engine and use a pump on the dipstick tube, that is what they were designed for.

 

[Fiveo Invader]

Re: 1989 Mercruiser 4.3

You know i thought about sliding a hose up to the drain plug since the hole where my cork thing goes is right there. I did find that the dipstick hole and pump seemed to be the most effiecent way. Much thanks.

 

[180shabah]

Re: 1989 Mercruiser 4.3

Those are more usless than a stringer drive powered by a 470!

Good one Don.

 

[Fiveo Invader]

Re: 1989 Mercruiser 4.3

Well it looks like Sunday is going to be the first day I hit the water. My bro and I want to get it out and test it. Anything I should be aware of? Its tuned and running very well. The timing is set and the carb is good. New gas and oil. Should I bring the whole tool box just in case? Ive never been in this postion before, my family always had new boats and a slip with mechanics. Lets hope all goes well..........

 

[Fiveo Invader]

Re: 1989 Mercruiser 4.3

HELP!!!! so much for gettin in the water. Does anyone have a clue as to how the rockers that are on top of the valve springs could be so loose that they move side to side almost 1/4 inch??? This awful racket came from the motor after I got it timed and tuned the idle. It is a loud clacking noise. I took the vavle covers off and there are the rockers banging around. what damage could this have caused? is it worth fixing if the motor needs to be redone?


Also, when I was testing the timing I checked each plug wire while it was running by removing it from the cap. the #6 wire made no change in engine running when removed as the others did. There is spark on the plug and its pretty black so I suppose there is combustion but have no idea why the engine would not change when the wire was removed.

You all have been great with the comments and help I hate to ask for more but I am at a loss. Thanks for any info thrown at me.

 

[Maclin]

Re: 1989 Mercruiser 4.3

The #6 cylinder could have a valvetrain issue (sounds like soon they all will have issues!). If the rockers for any cylinder are too loose to move the intake and exhaust valves enough then a cylinder will go dead. Opposite is also true, if the cylinder's valves do not close all the way because the rockers are too tight then that cylinder will go dead.

I think you found the "slight tapping noise" the owner described. There is something wrong with the valvetrain, something loose or not adjusted right or something missing that would keep the adjustment locked and it seems from your description that it is getting worse.

 

[Fiveo Invader]

Re: 1989 Mercruiser 4.3

well from reading the book ive got your right. the vale train is way out of adjustment i do have a dead cylinder (#6) i beleive it is from the lack of adjustment its a matter of time now to get it fixed with my schedule of midnights now. could this have damaged the cam with the lifters bangin around like they have been for probably 2 hours of run time since I noticed the first (tap) most likely the summer from what the owner before stated.

 

[Maclin]

Re: 1989 Mercruiser 4.3

Good point. Damage can have occurred to the cam lobes or the lifters or both. Impossible to tell without removing the components and inspecting. These symptoms can also be from collapsed or broken lifters, and it may be prudent to remove at least the lifters and inspect them, be sure to put them back in the same exact lifter bore that they came out of if you reuse them. If you find damage on them I would recommend a new cam and lifter set. If the lifters seem ok then figure out why the rocker adjustment is backing off, fix it and run with what you have for now. When I look at lifters I like to put them bottom to bottom to see if they are wearing flat or have a curve pattern wearing in. Make sure there is an oil film still on them before touching them together. You can also see problems if the metal is different colors across the bottom of the lifter, or if the surface has scratches nicks or other irregularities. You may also be able to see the cam lobes well enough to feel good about what you see or be disappointed.

You do not state if the engine was recently rebuilt or anything about the age, but if you suspect, after a recent rebuild, that this cam and lifter set was not broken in properly and "wiped" the cam lobes then you may want to consider new cam and lifter set. Usually cam lobe wiping happens quickly and in the very first part of the cam's life in the engine, so if this engine has been together for a while or is original then it is probably rocker adjustment locking failure of some kind.

 

[Coors]

Re: 1989 Mercruiser 4.3

Just a thought; is the oil pressure at least 40lbs?

 

[Fiveo Invader]

Re: 1989 Mercruiser 4.3

As far as a rebuild, i dont know. The motor has had work done but by someone who either didnt care of the outcome or by an idiot. I have fixed most of the problems but this one is out of my knowledge. What would cause the rockers to loosen so drastictly?

COORS- as for the oil pressure the guage is saying around the 40 psi mark.

As for the cam, I could inspect it pretty well from when i had the intake manifold off and it looked ok, no scratches or marks onthe lobes. The lfiters, i dont know with out tearing it down.

The guy that I bought it from didnt even know how to hook the battery up so maintance seemed to be shy on his part or if a mechanic stated something he just agreed. Ill start checking things and let you know. Thank you gentlemen, i appreciate the help.

Ken

 

[krisnowicki]

Re: 1989 Mercruiser 4.3

shouldn't any seriuos problems in the valve train shown in the compression test?

 

[PBKboater]

Re: 1989 Mercruiser 4.3

Hey guys Ken, After reading the whole post here could it be possible Ken has a timing chain/belt issue? I'm thinking eng was off-tuned (advanced/retarded) and once Ken set timing the valve lash really showed up! In any case when Ken sets valve lash back up should be obvious. I've seen where timing chain/belt off enough to create issues. Just an observation here!

Paul

 

[PBKboater]

Re: 1989 Mercruiser 4.3

OK never mind my stupid question, timing advancement or retardation has nothing to do with valve lash! "DUH" BUT, valve lash set up can be an issue ..ie not set at TDC Correct?? like post suggest?

Sorry Ken just trying learn also!

Paul

 

[Coors]

Re: 1989 Mercruiser 4.3

Ok, if the oil pressure is good, not collapsed lifters. Were the rockers adjusted before you got it? (maybe never right before?)

 

[Maclin]

Re: 1989 Mercruiser 4.3

I think you need to remove the rockers and pushrods and lifters. PBKboater brought up something then talked himself out of it but I think he had another good checkpoint. If the cam timing belt or chain is not timed correctly then the pistons could have canked the valves and bent the pushrods. You really need to determine if the correct hardware (rocker stud, nut and keeper) is in place and that the pushrods are not bent and that the lifters are not broken or collapsed. I had an engine that broke a lifter once, the oil pressure was not affected.

It is not too difficult to get the rockers, pushrods and lifters out, you have already had the intake off. At that point in time (intake off) if you just removed the rocker covers then removed the rockers and pushrods you could get to the lifters and remove them as well. But you may not have to take off the intake again if it is back on, I have snaked lifters out easily on other engines (have never worked a 4.3) without having to take the intake off. There are lifter removal tools as well as heavy magnets on a telescoping shaft that could probably get the job done.

Roll the pushrods around on a flat table. Look at the holes in the rockers to see if they are elongated or show cracking at the hole edges. Look at the ends of the rockers for excessive wear. Remove and inspect the rocker studs and the pedestals on the head they screw into. Be sure all of the parts are correct.

 

[BAYLINER185]

Re: 1989 Mercruiser 4.3

LOL Don

Thats what My dealer told me too when I bought my new BAYLINER 185. My Merc. already had one installed and I thougth it was cool. They said you need to at best hook up a pump to that and pump oil out.

My Cruser didnt have the hose so I bought a pump and I have used pumps on the dipstick before so I know it works and you can do an oil change and be back on the water in a few hours!