leakdown/compression test suggestion

[smittyseng]

I'm going to climb on my soapbox (as I have done in the past)-A good suggestion for everyone BEFORE they put there boat away for the winter-Do a compression test on your motor/motors in your boat before you finalize your storage prep for the winter. Find your weakest cylinder, screw the leakdown tester gauge that EVERYONE should own (they are only 40-75 $ at local autoparts store) in that particular cylinder and see what you got. If its unsatisfactory (20% is somewhat low-30% is real low) you will have all winter to address it INSTEAD of having problems at the beginning of next season that ruin your boating season!!!!! Another thing EVERYONE should think of doing in a ideal world (I have always done this) is after dynoing your motor or breaking in a new motor do both test on every cylinder,write down the numbers in your detailed notes you should be keeping for FUTURE comparison then later if you suspect your motor isn't running a 100% you will have a basepoint later on or something to compare your numbers to when doing your ANNUAL test! If your numbers are bad after breaking in or dynoing you know what you need to do too,Smitty

[2112]

Sage advice

[Chris]

Good advice. I do leakdown with the rockers off and the piston in 3 spots TDC, BDC and mid-point. Had a spirolock come loose once and score a cylinder- right in the middle. It hadn't done much damage at that point but it put a fairly decent gouge in the middle of the wall. But, it didn't get all the way up. I found it by setting the piston midway down and watched the leakdown tester drop like a rock.

Had I run it next year, It probably wouldn't have been noticeable... until the engine grenaded.

[Mrhorsepower1]

Sound advice bro.

[Elite Marine]

Great advice!!

[Strip Poker 388]

I just did A leak down on mine before I pull the motors,My puke tanks didn't have any oil in them from the full season,So I figure theres not much blow by. My 60 over motor was all between 6-8 %, the 30 over which I thought was better was 8-15% ,but the motor had cooled off by the time I did it,Ive never had a motor over 15% except when it had a hole in it at 50% I have a 2 gage set up ,set the base line at a 100psi, easy to figure from there.

I only test it at TDC,I'm I missing something?
Rob

[Elite Marine]

You got it Rob!

[Blue Thunder]

In addition, I like to cut open the oil filters that ran the last part of the season. Early warning of things going wrong is always good, particularly at the start of winter!

[Strip Poker 388]

Just wish there was a cleaner way than a hacksaw,without paying 50. for the can opener style.

[smittyseng]

In addition, I like to cut open the oil filters that ran the last part of the season. Early warning of things going wrong is always good, particularly at the start of winter!

I bought one of the premium filter cutters after using Crocketts at his shop a few years ago,we cut ALL my boat filters open everytime now,I have about 15 of the outer cans that we cut perfect that I'm going to figure out something nifty to do with someday,Smitty

[KENNYO]

I bought one of the premium filter cutters after using Crocketts at his shop a few years ago,we cut ALL my boat filters open everytime now,I have about 15 of the outer cans that we cut perfect that I'm going to figure out something nifty to do with someday,Smitty

Drink beer out of them!

[Mr Gadgets]

Summit racing has the cutters for under $40

Whats the perferred way to hold the motor at TDC and Mid point?

[smittyseng]

Summit racing has the cutters for under $40

Whats the perferred way to hold the motor at TDC and Mid point?

Ive always put motor at tdc and not had much of a problem with it coming off tdc. Anytime it was OFF tdc it's been very difficult to hold it while pressurising a cylinder,you could hold it with a breaker bar but don't let it get near you or it might knock your teeth out,Smitty

[RumRunner]

Always make sure when doing engine diagnostic work that you're checking at the same temperatures.

[Blue Thunder]

Both of my engines are now on stands in the garage. This resulted from what I considered an unacceptable amount of bearing material in the pleats of the sb engine. The other engines filter was flake free. I didn't plan on doing this work this winter either but as the OP says better during winter than summer!

FYI - I chisel/hammer my filters open and it is very easy to do with the filter in a vise.

[rssteiny]

What is the best temp to do the leak down at, full engine temp , or just warm

[HotPursuit]

Just wish there was a cleaner way than a hacksaw,without paying 50. for the can opener style.

Rob
I run System 1 oil filters they come apart and have a stainless element.I pull them after every hard run. Worth the $$$ in the long run ,you purchase once and never throw away. Dam does that mean Im going green

[HotPursuit]

What is the best temp to do the leak down at, full engine temp , or just warm

Cool enough so you dont burn ya fingers. I do mine cold..

[HotPursuit]

Systen 1

[Blue Thunder]

Systen 1

Theres the hot ticket! Do you have a link HP?