Time for Compression Check UPDATE

[FreeBeeTony]

Well....I replaced the plugs, cap and rotor today with no significant improvement. I didn't have a compresion gauge.....but will have one tomorrow.<br /><br />I will be checking the compression tomorrow.<br />I plan on removing the coil wire and doing one plug at a time........<br />If the compression looks ok (which I hope it does), I am going to get a rebuild kit for the carb. I also replaced the water seperator. How can I tell if I have bad gas?<br /><br />Ant suggestions will be appreciated.

 

[jeff13601]

Re: Time for Compression Check UPDATE

It starts looking foggy. How long has the gas sat in the tank?

 

[Bondo]

Re: Time for Compression Check UPDATE

Hi Tony,........ I guess you Did It,..?? Huh,...??<br /><br />That should be a Great Up-Grade for You,.......... <br />Any Bites on the Old, Totally Rebuild, Re-Engineered, Grady,..??? Too Bad,... You Just got All the "Bugs" out of it,........... <br /><br />You really Should pull All the plugs,+ make Sure the choke plates,+ throttle plates are Wide Open, to get a "Real Compression Test",...........

How can I tell if I have bad gas?<br />

Smell It,................ <br /><br />If it Smells like Gas, It'll burn Just Fine,..........

 

[FreeBeeTony]

Re: Time for Compression Check UPDATE

hey bondo.......glad to see you!<br /><br />I changed the water seperator.it smelled like gas.<br /><br />The secondaries don't appear to open if the throttle is open w/o the engine running. Are the secondaries mechanical? Could this be my problem?<br /><br />Why would all the plugs need to be removed? I'm really looking for a catastrophic failue...but I really don't think it's internal. I am hoping it's fuel. How about the timing of this thunderbolt ignition? Any tricks on checking it? I am looking for all the help I can get here!<br />Any hints for me?

 

[Don S]

Re: Time for Compression Check UPDATE

Here is the procedure for doing the compression test. Do all the steps and it will tell you a lot.<br /><br />Compression Test<br /><br />PS, just went back and found your old post to find out what engine you have..... I can't remember that kind of stuff. Anyway, you might want to add to your signature or something that you have a 92 Mercruiser 350 Mag engine.<br /><br />As far as the secondaries on your carb, which carb do you have.<br />Here is an online link to YOUR engine, use it to ID the different things you have on your engine.<br /><br /> Part List

 

[Bondo]

Re: Time for Compression Check UPDATE

2ndaries are Vaccuum......<br /><br />The motor Breathes,+ Turns Over better with the Plugs Out,+ the Throttle,+ Choke Wide Open..........<br /><br />T-Bolt IV is just timed at the rpms,+ *s needed........<br />T-Bolt V needs a wire grounded to time it.........<br /><br />I'm going to go,+ wander thru My Shop Manuals,..........<br />I've got book 1 of manual 17 here in my hand,... book 2 should be in the box,...... Maybe I've got doubles,.....<br />Let Me see what I've got,...... Maybe I can scan it,+ email you the files....??....

 

[Trent]

Re: Time for Compression Check UPDATE

Me thinks Freebe needs a manual....

 

[Don S]

Re: Time for Compression Check UPDATE

Hey Bondo..... he needs book 15, not 17.

 

[Bondo]

Re: Time for Compression Check UPDATE

Originally posted by Don S:<br /> Hey Bondo..... he needs book 15, not 17.

In That Case,............ He's SOL..............

 

[Don S]

Re: Time for Compression Check UPDATE

And I can already see it coming. $35 for a Clymers..... oops it ain't worth sheet. Then another $35 for a Seloc.....oops, it ain't worth sheet either. Then $71 for a Merc manual....... ahhhhhhh. Total cost $141<br />Saying "I Told You So" in about 2 months..... Priceless

 

[FreeBeeTony]

Re: Time for Compression Check UPDATE

Thanks for the help guys........think I am going to need it!<br /><br />After looking at the parts list from Don, I think I have a Weber Carb

 

[FreeBeeTony]

Re: Time for Compression Check UPDATE

Tried to add signature.......

 

[Bondo]

Re: Time for Compression Check UPDATE

I think I have a Weber Carb

That's a Big Plus in My Book,.............<br /><br />Simple Carb. to work on,........<br /><br />Buy the Gaskets,+ other parts for a Carter AFB Carb.,..........<br />Inexpensive,+ Easy to Find parts..........

 

[FreeBeeTony]

Re: Time for Compression Check UPDATE

What is an AFB carb? <br /><br />Is there a Sierra Kit available?<br /><br />I don't think the Mercruiser dealer in my area is open tobay........but BoatUS is!

 

[Bondo]

Re: Time for Compression Check UPDATE

Originally posted by FreeBeeTony:<br /> What is an AFB carb? <br /><br />Is there a Sierra Kit available?<br /><br />I don't think the Mercruiser dealer in my area is open tobay........but BoatUS is!

Carter AFB,....... Aluminum Four Barrel,.......Same Carb. as the Merc/Weber,+ the Edlebrock Performer Carb......<br /><br />NAPA has the Kits,......<br /><br />Federal Mogul,.. Performance Parts, Carter Kit # 902-317A..........<br /><br />NAPA or Seirra #s are 18-7748 or 18-7749,.. I can't tell Which 1 it is,....... I Do Know the Replacement Carb. is 18-7614.........

 

[FreeBeeTony]

Re: Time for Compression Check UPDATE

GREAT NEWS!!!!<br /><br />Compression numbers:<br /><br />#1- 170, 2- 165, 3- 160, 4- 150, 5- 170, 6- 140, 7- 160, 8- 140<br /><br />I did the test as said in the procedure Don posted, all plugs removed and open throttle w/ coil wire shorted.<br /><br />Now on to the carb.......I will probably start a new post once I get the kit. Having a party for my son today, graduating out of 8th grade....<br /><br />Thanks again guys........

 

[jeff13601]

Re: Time for Compression Check UPDATE

Congratulations on the test and to your son......