Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   Engine tick/knock? Please help!!! (https://www.offshoreonly.com/forums/general-q/241323-engine-tick-knock-please-help.html)

MILD THUNDER 10-27-2010 10:39 PM


Originally Posted by fkboatman (Post 3240516)
that really sucks, another big block that had the cam for dinner. does anyone know how they where broke in. did they use joe gibbs or other brand to break them in? remember break in break in is very important.

Normally not really a issue with rollers. Flat tappets, for sure. Sounds to me its more of a issue with those cams and the solid lifters and the setup.

rob vanharten 10-27-2010 10:52 PM

Thanks for the advice guys. At this point if the bottom end is good and I can drop $1500.00 on each motor with new cams lifters push rods and a oil change or two I would be happy. Just trying to put a game plan together at this point. I know both motors are coming out before the boat goes to sleep for the winter, so i can have new parts installed in both and be ready for spring. I would be really pissed if this was june. As far as the cams, I do not need them to sit there and almost die at an idle, but when I pull into a channel at idle I want to turn heads cause they sound mean. The 731's in my opinion sounded to close to stock, if not stock. Just looking for something that sets me apart from the croud. With a little attitude:)

MILD THUNDER 10-27-2010 10:59 PM


Originally Posted by rob vanharten (Post 3240551)
Thanks for the advice guys. At this point if the bottom end is good and I can drop $1500.00 on each motor with new cams lifters push rods and a oil change or two I would be happy. Just trying to put a game plan together at this point. I know both motors are coming out before the boat goes to sleep for the winter, so i can have new parts installed in both and be ready for spring. I would be really pissed if this was june. As far as the cams, I do not need them to sit there and almost die at an idle, but when I pull into a channel at idle I want to turn heads cause they sound mean. The 731's in my opinion sounded to close to stock, if not stock. Just looking for something that sets me apart from the croud. With a little attitude:)

The 741's have a bit more duration, so they will idle a bit lopy'er. Going to full dry exhaust will make it more crackly if thats your thing. You dont wanna go to crazy with duration, as the low end power will suffer, to get max HP you'll have to sping 6k rpm, and unless you have full dry exhaust, reversion is a problem.

The 741 should make nice power, and prop the boat to turn 5400-5500RPM max which is still ok for the hyd roller lifters.

MILD THUNDER 10-27-2010 11:01 PM


Originally Posted by mrfixxall (Post 3240541)
you say the engines only have 5 hr's on them? talk to the builder and see if theirs any warranty!! also cut open the oil filter on the other motor and compare the metal particles,could be from brake in..if the cam is going south it usually starts at the top of the lobe and not the side..

as for your next cam talk to bob madara @ marine kinetics,he is to cam god on here..

Saw you called the other night, goin to bed now, call ya tomorrow and catch up a bit bro....

dennis r 10-28-2010 04:38 AM

Rob I did a procharger motor with that 741 cam in a friends boat. We made 812 hp with 7 psi of boost so I know that cam will work.He runs the gill manifolds on it with no problem

RunninHotRacing163.1 10-28-2010 07:19 AM


Originally Posted by MILD THUNDER (Post 3240537)
I would go with the crane 168741 cam. Its a bit more aggressive than the ones you have now, and work very well with blowers. I would skip the prochargers, and stick with a roots style blower. I know too many guys with prochargers and spend lots of hours trying to get them to work properly. Once setup they make lots of power, but theres a reason all the big builders are still using roots blowers even on 1000+hp marine motors.

Introduce yourself to jimv. he is close to you. Let him help you get your motors straightened out. i agree you should switch to hydraulic roller lifters.

For all you know, you could have valve springs binding, too stiff of valve springs, etc. JimV will be able to get you going in the right direction.

Sucks, but at least you have all winter to go thru them, and come spring, you will have some bad a$$ motors. Hopefully you maybe just need fresh bearings in the bottom end. The cam material will get in them. Hopefully you cought it fast enough where the crank/rods didnt get hurt. It sounds like you'll be ok.

Introduce yourself to jimv. he is close to you. and 1 of the nicest guys you'll ever meet
+ 1 :drink::drink::drink::drink:























A lil story 4 ya :eek: Jimmy Valako drove 3.5 hours to deliver a set of heads to the shop last July and after talking with my son for a bit wanted to take a look at the ATECO rebuilds he just picked up from Waukegan and take a look at the bad cam that was replaced ,after inspecting the bad cam he went further & checked the lifters only to find the bad lifter was still in the bore ready to munch another cam :eek: all the lifters were removed & a new set of lifters was ordered & installed and a major catastrophe headed off .. meet Jim for lunch and a beer you'll be glad you did :drink:

rob vanharten 10-28-2010 06:51 PM

Just got of the phone with Jim. What a great guy, explained everything to me in detail, and helped me understand what was probably going on with this engine. Looks like both motors are getting pulled and dropped off at Jim's for a little upgrade:) After talking wiith Jim I feel very confident that we will have these motors figured out and rocking, not to mention not having to cross my fingers everytime I turn the key. Thanks Jim!!!

MILD THUNDER 10-28-2010 07:24 PM


Originally Posted by rob vanharten (Post 3241297)
Just got of the phone with Jim. What a great guy, explained everything to me in detail, and helped me understand what was probably going on with this engine. Looks like both motors are getting pulled and dropped off at Jim's for a little upgrade:) After talking wiith Jim I feel very confident that we will have these motors figured out and rocking, not to mention not having to cross my fingers everytime I turn the key. Thanks Jim!!!

Good deal! Keep us updated.....

dennis r 10-28-2010 08:00 PM

Your welcome rob with all the help.If I would have knowing you would give the work to someone else I would not have come over on a Sunday afternoon

rob vanharten 10-28-2010 08:42 PM

I am sorry Dennis, I did not realize you where viewing it as a job interview. I valued your opinion, and you live so close I did not think it would be a big deal for you to stop by when ever it worked best for you. I thought it was more of fellow boater kind of thing. I never ment to offend you. I am happy to pay you for your visit. I did not think you where set up to do all the work that Jim and I discussed. I am sorry Dennis!!!!!


All times are GMT -5. The time now is 07:06 PM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.