990's + Logs = Exhaust Leak??

« **on:** August 23, 2010, 06:32:25 PM »

I have a set of 990s w/ harman marine logs and looks like they dont line up what so ever. theres a good 1/8" gap....BUT its only on the drivers side. Passanger side is ok.

is this known with this combination or what?

should I change to a different set of logs? I would LOVE center rise setups, but thats a whole hell of a lotta coin i dont have.

this is a picture of the gasket on the log. the gasket fits the head correctly.

« **Reply #1 on:** August 23, 2010, 07:18:49 PM »

Has it always had an exhaust leak? Pretty weird........V-drive log maybe? Dun have any BBC logs here else I'd send one to try anyways......

Ray

« **Reply #2 on:** August 23, 2010, 07:34:55 PM »

this the 3rd set of 990's these logs have been on.....#1 didnt leak....but #2 leaked...as well as this third set.

i thought they maybe got warped and needed to be milled, so i pulled them off and noticed this. my plug wire boots dont stand a chance against this leak. the gap is on all 4 cylinders, but only on the drivers side.

« **Reply #3 on:** August 23, 2010, 08:10:10 PM »

You must have two passanger side heads

J/K Looks like a bastard log to me

« **Reply #4 on:** August 23, 2010, 08:29:44 PM »

try shit canning the gaskets.....little red on there.

maybe run a straight edge accross the mani.

« **Reply #5 on:** August 23, 2010, 08:58:17 PM »

Quote from: cj222 on August 23, 2010, 08:10:10 PM

You must have two passanger side heads J/K Looks like a bastard log to me

LOL! I actually processed that same thought before I posted!

But where I was going was with a passenger side v-drive log, but probably still way off on that.

Check with Terry, I think his buddie Jay has, or had, a couple sets of center risers he was lookin to sell......

Ray

« **Reply #6 on:** August 23, 2010, 09:22:53 PM »

I think Stevie Wonder drilled the holes and was being helped by Ray Charles.......Slot the holes....Or drill them bigger and use some hardened washers... $:-\$

I don't know...We had a set of Kodiaks on a cruiser. Save your pennies.

http://www.kemequipment.com/engparts%28exhaust%29.html

GT

« **Reply #7 on:** August 23, 2010, 09:32:10 PM »

Check with Terry, I think his buddie Jay has, or had, a couple sets of center risers he was lookin to sell......

Ray
[/quote

Hey thats right I do......and I have a BBC cruiser now too

« **Reply #8 on:** August 24, 2010, 05:22:56 AM »

Quote from: HDriderTH on August 23, 2010, 08:29:44 PM

try shit canning the gaskets.....little red on there.

maybe run a straight edge accross the mani.

they arent warped and its not an issue with gaskets. the ports arent lining up.

i think its time to invest in some through transom bassett headers. might be a cheaper route then center risers. I just dont know if they will fit under my engine cover.

if anyone see's a set out there for sale, let me know.

« **Reply #9 on:** August 24, 2010, 08:00:19 AM »

Quote from: Brad @ SCJB on August 24, 2010, 05:22:56 AM

they arent warped and its not an issue with gaskets. the ports arent lining up.

i think its time to invest in some through transom bassett headers. might be a cheaper route then center risers. I just dont know if they will fit under my engine cover.

if anyone see's a set out there for sale, let me know.

B-rad....Any chance you can get a picture of the gasket side of the manifold with a gasket sitting on it? Or is it put together?

This has me curious how that could get as goofey as it looks... $:-\$

I have a brand new set of 1997 Mercruiser 454 exhaust manifolds, but they are iron and weigh a whole bunch...(probably close to 50# each)...They have never had water through them.

GT

« **Reply #10 on:** August 24, 2010, 08:10:55 AM »

that is the manifold with the gasket laying on it as it would be. the bolt in the bottom right is there just to line up the holes.

« **Reply #11 on:** August 24, 2010, 08:49:56 AM »

Hey weener, Jim Brock has a nice set of Dana center risers with the turn downs for like $600. TT Bassetts won't work for your boat, they're not meant to be run in an enclosed engine compartment, too much heat.

« **Reply #12 on:** August 24, 2010, 11:04:47 AM »

Quote from: GT Jets on August 23, 2010, 09:22:53 PM

Slot the holes

i think this is going to be my quick solution. i got a set of 990's on an upside down engine thats on a stand i can put studs in to test alignment.

for a home hack job, what do you suggest to slot the holes? I assume a drill bit of some sort. i guess i can snoop around home depot and see what they got.

« **Reply #13 on:** August 24, 2010, 11:45:56 AM »

Get a deburring tool from homo depot, they look like a rotary file, but short and with a 1/4" shank so it'll fit in your drill. Follow that up with rat tail file and you'll be golden

« **Reply #14 on:** August 24, 2010, 06:47:06 PM »

Quote from: Brad @ SCJB on August 24, 2010, 11:04:47 AM

, what do you suggest to slot the holes? I assume a drill bit of some sort. i guess i can snoop around home depot and see what they got.

If you have a regular old plunge router and a square bit you're in business....otherwise just use a regular drill bit and some old fashioned elbow grease...

GT

« **Reply #15 on:** August 24, 2010, 08:26:43 PM »

So i lined up the gasket on the manifold for where it should be....then marked the holes with a sharpie.

i elongated them with a file drill at first which was taking forever, so then i went to town on them with a plain ol' drill bit which worked better/faster

the final product...

tomorrow im going to do some port matching, these are horrid.

elongated holes...

« **Reply #16 on:** August 24, 2010, 09:23:44 PM »

Quote from: Brad @ SCJB on August 24, 2010, 08:26:43 PM

So i lined up the gasket on the manifold for where it should be....then marked the holes with a sharpie.

i elongated them with a file drill at first which was taking forever, so then i went to town on them with a plain ol' drill bit which worked better/faster

tomorrow im going to do some port matching, these are horrid.

Way more gooderer

GT

« **Reply #17 on:** August 24, 2010, 09:33:53 PM »

F**K those were Waaay off alignment

« **Reply #18 on:** August 24, 2010, 09:53:39 PM »

Quote from: cj222 on August 24, 2010, 09:33:53 PM

F**K those were Waaay off alignment

I think those are Magoo Racing Products manifolds.....

« **Reply #19 on:** August 25, 2010, 07:17:23 AM »

so i woke up last night thinking about these damn things....

the plan was to start hacking away those chunks of metal blocking the ports......but i had this vision of them being thin areas and cutting into the water jacketing.....rendering these logs useless.

so, im gunna leave them alone. better safe than sorry. i got a line on some center risers that might fit under my engine cover, but for now, these will do.

« **Reply #20 on:** August 25, 2010, 03:47:57 PM »

I think the casting guy fell asleep when he made that side. You may have issues with the ports not lining up. I know 990's weak spot is in the exhaust ports. f it as long as your not running gobs of nitrous.

« **Reply #21 on:** August 25, 2010, 03:52:50 PM »

Quote from: ROMPERSTOMPER on August 25, 2010, 03:47:57 PM

I think the casting guy fell asleep when he made that side. You may have issues with the ports not lining up. I know 990's weak spot is in the exhaust ports. f it as long as your not running gobs of nitrous.

i have to agree....if i wasnt in a crunch for time, i'd pull the other side off to compare

« **Reply #22 on:** August 25, 2010, 08:23:41 PM »

well, so far this was a success. no leaks.

« **Reply #23 on:** August 25, 2010, 09:17:03 PM »

Brad @ SCJB

IRRebel

Brad @ SCJB

MADSKILLZ

HDriderTH

IRRebel

GT Jets

HDriderTH

Brad @ SCJB

GT Jets

Brad @ SCJB

Luckie Stiff

Brad @ SCJB

Luckie Stiff

GT Jets

Brad @ SCJB

GT Jets

MADSKILLZ

GT Jets

Brad @ SCJB

ROMPERSTOMPER

Brad @ SCJB

Brad @ SCJB

MADSKILLZ