454 magnum problems help please
#1
Registered
Thread Starter
Join Date: Dec 2007
Location: Palm Beach Gardens Florida
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
OK here goes, I have a 31 Scarab Excel with a pair of 454 mags that have had a lot of work done to the engines. New World product heads, and a crap load of other stuff to the tune of 28,000 for the pair. I just got the boat from the guy who had all of this work done. When I got the boat back to my shop one of my friends was looking atthe engines and could not believe what he saw. The guy I got the boat from spent all of this money on these engines to be built up and they left the stock intake manifolds on it. I just purchased a new pair of Merlin intakes (NICE) Well here goes my problem, I installed the new intakes and now the one engine cranks and will not fire. Obviously the timing is off. My first problem is I dont know how to determine the correct timing, I know it has the firing order on the old intakes but how do you check it??????? I know I am a dumbass. My second problem is with the other engine. When I removed the intake I noticed that a few of the valves looked a little rusty so I took them off and sent them out to be redone. My problem with this engine is I dont know how to set the valves. These engines have the roller rocker arms hydraulic lifters and all of that Jazz. I am sorry for such a long thread but I am killing myself trying to get the one engine to fire and I do not want to crank the other engine until I get the valves set properly. Any help would be greatly appreciated. It is killing me seeing this boat on the trailer when I should be burning up the intracoastal.
#2
Charter Member # 55
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
First of all, the stock magnum intakes are pretty good. They could have been reworked and matched to the engine also. I see no reason to have switched them in the first place, especially if you don't know what you're working with.
I highly doubt this guy spent 28k on the engines. You can buy a pair of 500hps with exhaust and have them installed for that money.
How did you put the distributors back in????? If they are off very much you're gonna get huge back fire or flames out the carb. Do you have any idea of how to set the timing from scratch?????
You can't take out valves without pulling the heads, so I have no idea what you are talkng about.
All of this stuff is difficult to explain, but is relatively simple to do or show you how to do in person.
I highly doubt this guy spent 28k on the engines. You can buy a pair of 500hps with exhaust and have them installed for that money.
How did you put the distributors back in????? If they are off very much you're gonna get huge back fire or flames out the carb. Do you have any idea of how to set the timing from scratch?????
You can't take out valves without pulling the heads, so I have no idea what you are talkng about.
All of this stuff is difficult to explain, but is relatively simple to do or show you how to do in person.
#3
Registered
![Default](/forums/images/icons/icon1.gif)
Don't take this the wrong way, but I think you should take the boat to someone who knows what they are doing before you do another 28,000 in damage. It is not very hard nor expensive to fix if you know what you're doing, but it is very easy to screw up. You are obviously not a mechanic, so take to someone that is. As Griff said, it is not easy to explain in words in a reasonable amount of time. I'm not trying to kick you in the ball bag, I just don't want you're second post to be that the rods are hanging out the block. I know this isn't what you want to hear, but I hope it helps, Eddie.
Oh, by the way, welcome to OSO.
Oh, by the way, welcome to OSO.
#4
Registered
Thread Starter
Join Date: Dec 2007
Location: Palm Beach Gardens Florida
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
When I said remove the valves I am sorry I meant remove the heads and had them reworked. As I said a couple of valves were a little rusty. I marked the distributors before I pulled them but they would not go in the same way that they came out. I have been told that if you are off 1 tooth on the gear it wont run properly and that is what scares me. As far as setting the timing from scratch I am not really sure but I am all over the internet trying to find out how to do it.I know I should have left the damn thing alone but I was told by more than one person that the exhisting intakes were killing the performance of the engine. As far as how much the guy actually spent on beefing up the engines I dont know for sure but I know the thing has top of the line everything in these engines. I got the boat really cheap and I just want to get it back in the water. Thanks for your help.
#5
Charter Member # 55
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
Yes you should have or at least known what was wrong or needed to be done.
You tore your engines down because a couple people said the intakes were killing performance??? Do these people build marine engines???? How do you know they have "top of the line everything" Do you have build sheets???? Post the specs and parts used. 28k does not buy top of the line for 2 engines.
If the valves were rusty, then something caused them to get that way--like water intrusion. How did you see that they were rusty???
.......and how did you put the heads back on??????
You don't just put the gasket on and tighten the bolts. Depending on what heads you have and what Generation the engine makes a difference. You need to torque the bolts in a specific order and in increments. The head bolts also need a lubricant or sealer depending on if they go into water ports.
As far as marking and putting the distributor back in---was the cap off and was the rotor pointing to the same cylinder when reinstalled????
If you want these engines to run well, or at all, for any length of time, you better take it to someone that works on hp marine engines and break out your checkbook.
Post where you live and maybe somebody can recommend someone.
You tore your engines down because a couple people said the intakes were killing performance??? Do these people build marine engines???? How do you know they have "top of the line everything" Do you have build sheets???? Post the specs and parts used. 28k does not buy top of the line for 2 engines.
If the valves were rusty, then something caused them to get that way--like water intrusion. How did you see that they were rusty???
.......and how did you put the heads back on??????
You don't just put the gasket on and tighten the bolts. Depending on what heads you have and what Generation the engine makes a difference. You need to torque the bolts in a specific order and in increments. The head bolts also need a lubricant or sealer depending on if they go into water ports.
As far as marking and putting the distributor back in---was the cap off and was the rotor pointing to the same cylinder when reinstalled????
If you want these engines to run well, or at all, for any length of time, you better take it to someone that works on hp marine engines and break out your checkbook.
Post where you live and maybe somebody can recommend someone.
Last edited by Griff; 12-17-2007 at 12:51 AM.
#6
Registered
![Default](/forums/images/icons/icon1.gif)
Alamo, seriously, stop now before you cause more damage. It is obvious you are not a mechanic. There is a reason that the valves looked the way they did. You have to find out why before you continue.
Different people have different ideas about what "top of the line" parts are. My "top of the line" parts will cost a LOT more than 28K for a pair of engines. They may have some decent parts in them, so don't ruin them by making a mistake. Take it to someone. There are a lot of really good builders on this site. Tell us where you are and we can recommend someone.
Eddie
Different people have different ideas about what "top of the line" parts are. My "top of the line" parts will cost a LOT more than 28K for a pair of engines. They may have some decent parts in them, so don't ruin them by making a mistake. Take it to someone. There are a lot of really good builders on this site. Tell us where you are and we can recommend someone.
Eddie
#8
Charter Member #927
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
I take it you just bought the boat and the guy that sold it to you said he had that much into the engines? Is that correct?
If someone built the engines for you, you should be able to tell us from the reciet what parts he used.
Welcome to OSO
If someone built the engines for you, you should be able to tell us from the reciet what parts he used.
Welcome to OSO
#9
Registered
Thread Starter
Join Date: Dec 2007
Location: Palm Beach Gardens Florida
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
OK as you all have figured out I am not a mechanic for I/O engines. I have worked on several outboard engines. As far as who is giving me the info it is a friend of mine that now lives in Ohio. He is a certified mechanic and he was the one that suggested the intake replacement. As far as the few valves being a bit rusty, they were rusty because water got into the engine from a bad head gasket. Yes I did torque the heads properly. I did not just slap a gasket on and tighten the hell out of the head. If you all think that it cant be explained on how to time the engine then I thank you for your help. I guess I will take it to a pro. Time to spend some more cash! Merry Christmas!!!!!!!!!!!!!!!
#10
Registered
Thread Starter
Join Date: Dec 2007
Location: Palm Beach Gardens Florida
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
I do see by the balancer there is a line across it and there is a little metal peice that has several markings like 4 2 0 8 12 16 I would guess if I line up the #1 cyl at TDC and retime the engine by the firing order. Is that correct or is that wrong as far as timing the engine? This will be my last stupid question. I am sorry that I am not as experienced as most of you but I would like to learn how to work on these engines. Also I contacted the guy that I got it from and got a copy of the receipt from the engines. It was 16500.00 not 28000.00 If it would help you guys to know what he put into it I can list all of the crap on this list. It is a long list. The weird thing and it almost scares me is that the shop that did the work only charged 75.00 per hr. in labor. That seems a bit low to me.