1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Get proper plugs

Adjust both sides

Temp gauge should tell you if at operating temp, 15 min should be enough

Pictures are pretty small, looks like you at the very least have a roller ready block.

Easiest way for you to tell now by checking something and reporting back here is a bigger picture or just pull a push-rod and tell us how long it is. This really make no difference in you getting it running well.

Get the actual part number on the head the next time you have the cover off.

Distributor is potentially dangerous, looks like it is not a marine unit. It wont prevent you from setting the valves but i wouldn't take it out on the water.

I actually bout a new ignition system http://www.michiganmotorz.com/delco-...tor-p-119.html should be here on tuesday when i get home from work. I will try to enlarge the picture and repost it ( trying to avoid cracking the intake manifold off if at all possible). I did have to pull the vaccume advance off on the distributor in order to get the valve cover off and a brass plug on the inside of the exhaust manifold. Wonder if the vaccume got messed up when i pulled it off. :facepalm:
This thing is turning into a major headace lol just like everything else i own at the moment seems when one thing goes everything follows in suite.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

coopin - Too me that motor just doesnt sound right. What i would be worried about is no oil coming out of the pushrods.

It should be squirting oil everywhere, especially if the motor had be running for 15 min.

Thats why it is so noisey!

Me personally i would not start it anymore untill i found out why!

When i tightened the lash the oil started spitting more. How much should the oil be squirting at 650-700 rpm's. If by chance the motor wasnt at operating temp would it be that slow?

It doesnt sound right to me either so agrivating.

I did start it for a bit today to mess with some vacume hose leaks (sounds a lil better not much) It ran for about 10 min ... tep guage on dash still said 120 like it hadnt moved. manifolds were warm to touch but not hot (not sure if they are supposed to be like that)

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

I would get it up to temp, run the valves. Then rev it a little and see if it doesn't push a lot more oil out. If not you might have other problems.

If you wan to be safe, pull the other cover and see if oil delivery is the same on the other side. Tell us what you find.

 

[81 Checkmate]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Its not gona squirt you in the eye while you looking at it. but you should get a good flow out of the pushrod oil holes. Then it should puddle up on the rocker then flow over into the head.
After 5 min of run time you should have an oily mess.

Just think when people have a valve cover gaskets leaking, there is oil running down the side of the block and pooling ontop of the intake.
Thats how much oil should be flowing!

Not to be a bummer but i think Don has a point. As his sig say's The Oracle by the Sea, Have you seen his Beard!

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Its not gona squirt you in the eye while you looking at it. but you should get a good flow out of the pushrod oil holes. Then it should puddle up on the rocker then flow over into the head.
After 5 min of run time you should have an oily mess.

Just think when people have a valve cover gaskets leaking, there is oil running down the side of the block and pooling ontop of the intake.
Thats how much oil should be flowing!

Not to be a bummer but i think Don has a point. As his sig say's The Oracle by the Sea, Have you seen his Beard!

A fresh engine with tight clearances and maybe a high volume/high pressure oil pump will squirt oil every where. A well broke in engine idling at 600 rpm... not so much.

Don might yank it, but he is fully equipped to do so. As he has said many times, he can have it out and on the floor in under an hour. Most noobs would spend all day doing the same, after beg stealing and borrowing all the stuff to do so.

A poorly tuned engine can make all kinds of clatter. I think a little more tuning is in order.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Its not gona squirt you in the eye while you looking at it. but you should get a good flow out of the pushrod oil holes. Then it should puddle up on the rocker then flow over into the head.
After 5 min of run time you should have an oily mess.

Just think when people have a valve cover gaskets leaking, there is oil running down the side of the block and pooling ontop of the intake.
Thats how much oil should be flowing!

Not to be a bummer but i think Don has a point. As his sig say's The Oracle by the Sea, Have you seen his Beard!

LMAO yeah I know Don is prolly gunna be right in the end but im crossing my fingers and toes hoping that i can get it to make it through this summer without pulling it :facepalm: so many other financial priorities. Anyway After they ran for a while the oil did seem to flow a little better. I will take it all apart again tomorrow Both sides adjust all valve lash and post another video of all of it and see where I stand. Will go ahead and change to correct plugs as well. I will update you guys again tomorrow evening. And checkmate I understand now about the valve cover leaks makes sense just havent messed with these all that much before. Again to all thanks for all the input and i will keep you updated.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

A fresh engine with tight clearances and maybe a high volume/high pressure oil pump will squirt oil every where. A well broke in engine idling at 600 rpm... not so much.

Don might yank it, but he is fully equipped to do so. As he has said many times, he can have it out and on the floor in under an hour. Most noobs would spend all day doing the same, after beg stealing and borrowing all the stuff to do so.

A poorly tuned engine can make all kinds of clatter. I think a little more tuning is in order.

God I hope so and yeah it would prolly take me all weekend to pull it considering wife and kid duties. plus would have to rig something up to pull it as i know my chery picker is not tall enough. :/

 

[81 Checkmate]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

You could be right Joe, it's to bad coopin does't know the history of the boat. that would tell the tale.

Yes if the rockers are not tuned right the oil pressure would be differnt, but in the video he has no oil flowing, maybe a spit or two and thats not right.

I think someone put a refubished motor in it and thunder bolt module was bad so they stuck the auto dist in it to get it running to sell.

Or could have replace the heads becouse of a crack and didnt know how to tune it.

Just a thought, Good luck coopin

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

You could be right Joe, it's to bad coopin does't know the history of the boat. that would tell the tale.

Yes if the rockers are not tuned right the oil pressure would be differnt, but in the video he has no oil flowing, maybe a spit or two and thats not right.

I think someone put a refubished motor in it and thunder bolt module was bad so they stuck the auto dist in it to get it running to sell.

Or could have replace the heads becouse of a crack and didnt know how to tune it.

Just a thought, Good luck coopin

You just never know with used stuff...
The rockers have oil pooling in the cups, (I have a rather large monitor, easy to see) its just not shooting as is usually the case. I completely agree that the oil flow looks questionable and i mentioned that in my second post.

 

[tpenfield]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

I rebuilt my 454 Mercruiser last Fall, and started it up with the valve covers off. Initially, the push rods/rocker arms did not spit too much oil, but after a while, it was squirting me in the eye. So, I had to put the valve covers back on.

Your engine does sound 'clattering' . . . Are you sure that you have the valves adjusted properly?

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

I rebuilt my 454 Mercruiser last Fall, and started it up with the valve covers off. Initially, the push rods/rocker arms did not spit too much oil, but after a while, it was squirting me in the eye. So, I had to put the valve covers back on.

Your engine does sound 'clattering' . . . Are you sure that you have the valves adjusted properly?

No I probally do not have them adjusted correctly but when I get home from work this evening I will go ahead and set all of them both sides after the motor warms up (gunna let it run for about 15-20 min this time using stop watch) see where im at count all of the threads on each stud and post my results as well as a video so you guys can take another look and let me know what you think. I wish I knew the history of the boat a lil better myself. The guy I purchased the boat from had the boat for about 3-4 years said the only reason he was selling it was because he bought a bigger boat (As I pulled the boat out of the slip he put his new 34 footer in there) I got a decent deal on the boat or so I thought at the time (hopefully this holds true). He did say that the outdrive was completely rebuilt at the begining of last season to a tune of $2200 but other than that I dont know much of the history . Either way its mine now and gotta get her right so its not only running well but also safe. But at least now I know that at a minimum the heads were replaced at some time.

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

As you back them off and they start to clatter... let each one clatter for a few seconds to see if the clattering goes away. If it does back it off some more. If some of the valves are too tight, as you back them off they will clatter but then the lifter will pump back up and the clatter might go away. Based on the way your rocker heights look i am guessing you have some that are loose and some that are too tight.
good luck

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Thanks joe I will post results tonight and let you know.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Joe

Going to go grab those new plugs on my lunch break but quick question on that topic. Should the new plugs be gapped the same or is there a different spec if so what is the gap supposed to be set at? Do any of these plugs come pre gapped?

 

[tpenfield]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

FWIW - I tried adjusting the valves on my Mercruiser with the engine running with limited success, just because the engine itself is noisey and I am getting more deaf as I get older. So, I could not really hear when when they were reaching zero lash. Plus, oil was starting to go all over the place . . . even got some in my beer.

There were 2 methods in the Mercruiser manual for adjusting valves - "with the engine running" and "while the engine is stopped". I finally used the 'stopped' method and it worked out much better.

I'm not sure if your 5.7 has the same adjustment methods spec'd out in the manual, but it is worth mentioning.

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

I actually found these instructions http://forums.iboats.com/attachment.php?attachmentid=138820&d=1333057559 That don had posted on adjusting the valves so i printed them out and will do that this evening. But i do agree with you it is quite noisey. Especially mine right now as stated before sounds like crap. Hopefully I can get it to run decent without pulling it guess we will see

 

[joewithaboat]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Joe

Going to go grab those new plugs on my lunch break but quick question on that topic. Should the new plugs be gapped the same or is there a different spec if so what is the gap supposed to be set at? Do any of these plugs come pre gapped?

You should always check them, even though most come "pre-gaped"
The gap used depends mostly on your ignition type. I think i saw somewhere in your post that you had an HEI automotive distributor. That ignition is very hot at idle and will jump a big gap. However, I would still stick with your factory recommended gap because you plan on changing the distributor. It should be on the sticker on your black engine cover... probably .045

 

[coopin87]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

OK guys so i dug a little deeper into the motor today. Pulled both valve covers and adjusted all valve lash. I think I found my issue. After adjusting all im squirting oil much better now. Seemed like most of them were way over tight to quite a bit of backing off to get to zero lash (tightened all back 1/2 turn after zero). Anyway onto what i found on the right side number 5 rocker did not seem to be functioning at all. Well it was pushing valve down but not very much so i tighten in up a bit and still nothing got it to move a bit more but still not like the others. took it off and inspected push rod looks good and arm looks good so at this point im thinking that either i have a bad lifter or somthing is going on with the valve. Spring also looked good (kinda hard to see because manifold is right there. could this happen if i had no spark to #5? Any ideas?

BTW after adjusting all other valve lash the motor runs so much better now still need to put the new ignition system in but want to have everything else straight first.

 

[Don S]

Re: 1996 mercruiser 5.7 with thunderbolt ignition ... Top End knock Please Help

Well it was pushing valve down but not very much so i tighten in up a bit and still nothing got it to move a bit more but still not like the others. took it off and inspected push rod looks good and arm looks good so at this point im thinking that either i have a bad lifter or somthing is going on with the valve.

The cam is what determines how far the valve is pushed down, not the pushrod or lifter. If you bottomed out the lifter and the valve still moved very little, you have a wiped lobe on the cam.