Marine Engine Repair, Boat Engine Repair, Replace Boat Engine, Replace Marine Engines, Replace Engine Longblock

Get Free Mercury Gen II Shift Cables
I don’t normally throw out a lot of advertisements on our blog page but this is a pretty good deal. Mercury is currently giving away free Throttle/Shift Cables with the purchase of a 4000 or 4500 Remote Control. http://tinyurl.com/25e6tjr

How to Select a Better Propeller
Topic: Gear Ratio and Propeller Pitch Selection Guide. Question #1: How do I select the correct gear ratio and propeller combination when upgrading my current product? Response: There is no basic answer to this question while the reality is that nothing replaces having good data to review when making selections. No matter how much estimating and calculating [...]

Used Boat Sales
The latest report released by Soundings Trade shows that used boat “Brokerage” boat sales were down a little for July 2010 as compared with July 2009. Speaking for those of us here in the Mid-West, I suspect this is due to the lack of good, high quality used boats. With the new boat sales market still [...]

Installing Closed Cooling On An Old Engine
I’ve had at least 10 people ask me about this subject again this week. I’m not sure what’s triggered the rush on this subject again this week but thought I would go ahead and provide the link to where we addressed it again for those interested. The link on the website goes into detail regarding this topic [...]

When Will The New Boat Sales Market Recover?
The latest new boat sales data seems to indicate the same thing the new housing sales market did last week; people are still not willing to spend the extra money to purchase new versus used. Everything we can see points to the fact that investing into repairs of existing boats is very worthwhile since dealers are making [...]

In 2002 Mercruiser changed on the V6 and Small Block V8 engines from the standard style of exhaust to the newer Dry Joint Exhaust systems. The purpose of this was to reduce the risk of leakage at the gasket between the manifold and exhaust riser. It should also be noted that the height and down angle of the exhaust elbow changed as well. It was felt that the overall height of the exhaust elbow should be raised to meet the total height of the engine. Therefore Mercruiser created the 1.5" taller exhaust elbow which included a 14 degree down angle versus the standard 7 degree. This then created an issue regarding the use of risers. For example when 3" risers/spacers are installed along with the taller elbow this means the overall height of that installation was taller than the previous installation with 3" risers. Therefore Mercruiser created the 1.7" and 4.5" riser/spacer to account for these installations where the standard 3" & 6" spacers were already at a package height limit.

Short Dry Joint Elbow p/n 864309T02 s/n 309999 and below (pre 2005 models) - Measures 5.2 from elbow flange to mounting bolt bass pad. SELECT THIS LINK TO VIEW EXHAUST DRAWING.

Tall Dry Joint Elbow p/n 864591T02 s/n 310000 and above (post 2005 models) - Measures 6.7 from elbow flange to mounting bolt bass pad. SELECT THIS LINK TO VIEW EXHAUST DRAWING.

If you are trying to replace the standard type non dry-joint exhaust with the improved dry-joint system this is in fact possible, however you will most likely need to use the "short" Dry-Joint elbow/riser as this will be the closest fit to the old non-dry joint elbow/riser. The p/n for the restrictor style dry-joint gasket is 27-864850A02 (select link).

Mercruiser also had 2 different systems available on the 8.1L (496 CID) engines. Select these links to view the differences and associated systems.

Link to ........ V6 Standard Exhaust (serial number 0M614999 and below)
Link to ........ V6 Dry Joint Exhaust (serial number 0M615000 and up)

Link to ........ V8 Standard Exhaust (serial number 0M299999 and below)
Link to ........ V8 Dry Joint Exhaust (serial number 0M300000 and up)

Link to ........Stainless Riser Exhaust System
Link to.........Cast Iron Riser Exhaust System

Link to ........ 8.1L Exhaust with Water Rail
Link to ........ 8.1L Exhaust with W/O Rail

Technical Articles