Carb rebuild vs. spraying in carb cleaner

[gjmsd]

I have a 1975 Evinrude 135 that runs great at WOT, doesn't idle so well though. It has reasonable compression (125-130) on all cylinders so that doesn't appear to be the problem. I'm contemplating a carb rebuild but with only a month or two left of boating season here don't want to do to much to it now, I'd rather wait and do it during the off season. Question is, can I effectively spray carb cleaner into the orifices and jets without disassembling the carb? If so, where should I spray it?

 

[BonairII]

Re: Carb rebuild vs. spraying in carb cleaner

Nope...you have to disassemble. Carb cleaner will probably dissolve varnish, but won't get gunk and debris out.

 

[Haffiman]

Re: Carb rebuild vs. spraying in carb cleaner

Carb cleaner may dissolve gunk and build-up, but it does not remove it!

 

[ADK_Boater]

Re: Carb rebuild vs. spraying in carb cleaner

Cleaning the carbs (especially if you don't know the history of a motor) is never a bad idea. Yes, it does take the better part of a day. Possibly a full day if you've never done it before, but that's how it's done. After you've cleaned it, every once in a while you can give it a shot of carb cleaner with the silencer off to keep clean the few orifices you can reach .

 

[kfa4303]

Re: Carb rebuild vs. spraying in carb cleaner

HI gjmsd. I agree, you need to rebuild it, not just spary in carb cleaner, which may actually react with plastic components and do more harm than good. However, as far as the idle goes, you may want to try spraying a bit of seafoam into the carb while it's running at med-high idle. It smokes like crazy, but will often help smooth out the idle. look up "decarb procedure" and you'll see all kinds of threads/posts. best $10 you can spend on a motor.

 

[iwombat]

Re: Carb rebuild vs. spraying in carb cleaner

If it's just idling a little rough (not really badly), you may well have good luck with a seafoam gas treatment as mentioned above. If the seafoam can get to the problem (i.e. not totally clogged up), it's surprising what it can clean up.

It's worth a shot anyway. Run for 15mins, rest for 15mins, repeat . . . That'll let the product work it's magic if it's going to at all.

 

[Borgey401]

Re: Carb rebuild vs. spraying in carb cleaner

Seafoam does work pretty damn good. I used to to decarb my motor when I first got it. It smokes like crazy tho so be prepared for that LOL.

 

[gjmsd]

Re: Carb rebuild vs. spraying in carb cleaner

Thanks for the info, I'm familiar with seafoam gas treatment and use it on my off road stuff but was unaware they had a spray, I will definitely try it. The jets can't be totally plugged because it will idle, just not well.

 

[iwombat]

Re: Carb rebuild vs. spraying in carb cleaner

Just use the gas treatment. 1can : 1gal of gas. Use a small portable tank.

 

[boobie]

Re: Carb rebuild vs. spraying in carb cleaner

Agreed + 2. The carbs should still come off for a good cleaning after the above treatment tho'.

 

[kfa4303]

Re: Carb rebuild vs. spraying in carb cleaner

yup. you may want to clean/change the spark plugs afterwards too. They can get pretty dirty in the process, but it works wonders.

 

[boobie]

Re: Carb rebuild vs. spraying in carb cleaner

Shouldn't the plugs be cleaned by the same decarb process? If it runs allright, I'd leave them.

 

[gjmsd]

Re: Carb rebuild vs. spraying in carb cleaner

I just put in new center fire plugs so I know they are clean now. Gonna decarb tomorrow and I'll see how it runs afterward. I've used Seafoam for a while but only in small amounts mixed with gas for my off-road stuff. This will be the first time I'm trying it in heavy concentration (1 can per gallon) so I'm real curious how it works. I'll re-post after.

 

[Haffiman]

Re: Carb rebuild vs. spraying in carb cleaner

I just put in new center fire plugs so I know they are clean now.

Which plugs.
If you put in UL77, try the QL16V. Same type, but improves the idling.

 

[kfa4303]

Re: Carb rebuild vs. spraying in carb cleaner

If the plugs are brand new, you should be fine. Just be prepared for some serious smokage (seriously) You may want to forewarn the neighbors. Try to get the motor out on the water afterwards ASAP, so you can get her up to WOT and really get rid of the goop. You'll be amazed at the difference it makes. Keep us posted.


p.s.
some folks may find they need to change plugs after a decarb, if the original plugs were old and cruddy to begin with, but it's usually not necessary. I usually put new ones in afterwards b/c they're only $5 and just so everything is burning nice and clean.

 

[James R]

Re: Carb rebuild vs. spraying in carb cleaner

Poor fuel flow means poor lubrication so if you don't want to ruin your motor remove carb or carbs, strip them and soak the parts in Gunk Carb and parts cleaner. Comes in a gallon can with a cage for small parts. Save it and use again. Follow the instructions on the can. Rebuild with new Kits and all will be well.
Never, Never put spray cleaner near your carbs if you want them to live.

 

[gjmsd]

Re: Carb rebuild vs. spraying in carb cleaner

All I can say is, Seafoam is amazing. I did as suggested and put 1 can in a gallon of premix and ran it for 15 minutes. Took the usual amount of ether to get it started and had to run it at fast (and rough) idle to keep it going. Shut it down and let it sit for a few. When I barely touched the key, it fired right up and idle smoothly at low rpm. Unbelievable how much difference it made. Oh yeah, it did smoke a lot. I used Seafoam for a while but never like this. Always added a small amount to each tankful on my off-road stuff to keep it clean. Still shocked at what it can do. Thanks to everyone.

 

[iwombat]

Re: Carb rebuild vs. spraying in carb cleaner

Well, here's another tip - never use starter fluid to start a two-stroke. It washes all the lubrication down and causes undue wear. Instead, use a spray bottle with some premix.

Glad it's better though.