Big Twin starting problem

[drmbykr]

Old big twin,25hp I think.Won't turn over with spark plugs in.Removed plugs and turns over freely.
Ok,found out it is a 28 hp.I got SN# how can I find the year?

 

[kbait]

Re: Big Twin starting problem

Those are big compression motors.. May just be hard to pull. Or you have too long of spark plugs and they're hitting the pistons?

 

[bktheking]

Re: Big Twin starting problem

Those are big compression motors.. May just be hard to pull. Or you have too long of spark plugs and they're hitting the pistons?

No compression release on them as far as I know which would make them a bear to pull over, the 40hp with comp release damn near broke my arm last year after about the 5th pull. What plugs are installed?

 

[jasper60103]

Re: Big Twin starting problem

Old big twin,25hp I think.Won't turn over with spark plugs in.Removed plugs and turns over freely.

yep, my old 28hp was a hard pull.
Be sure to mount it on the boat as a stand will likely tip over when you pull.

 

[drmbykr]

Re: Big Twin starting problem

I will have to check on plug size.It has elect. and hand start,wont turn over with either unless plugs are out.Plugs dont show any signs off damage.
Anyone know where to get free service/repair manual?Boat belongs to a elderly man who doesnt have alot of money and I cant afford to buy him one.

 

[drmbykr]

Re: Big Twin starting problem

No compression release on them as far as I know which would make them a bear to pull over, the 40hp with comp release damn near broke my arm last year after about the 5th pull. What plugs are installed?

I will have to check on plug size.It has elect. and hand start,wont turn over with either unless plugs are out.Plugs dont show any signs off damage.
Anyone know where to get free service/repair manual?Boat belongs to a elderly man who doesnt have alot of money and I cant afford to buy him one.

 

[bktheking]

Re: Big Twin starting problem

You can put a want ad up on the webvertize portion of AOMCI.ORG and see if you can buy a manual on the cheap.


Here is a link to a parts list for what may be your motor:

http://www.aomci.org/cgi-bin/yabb2/YaBB.pl?num=1264108546/2#2

It's a starting point, says it calls for a Champion j6j plug which is replaced by j6c.

 

[F_R]

Re: Big Twin starting problem

If it is an "old" Big Twin 25hp, it probably is a 1955 or older, right? They had 6 volt starters and they weren't the most powerful starter even when new. Many people back then used an 8 volt battery for better starting. Well, that was then and this is now, and 8 volt batteries aren't exactly commonplace. So many people now use 12V battery. It won't hurt the starter if you don't stay on the start button forever. The choke solenoid may be a different story. You really should put a voltage dropping resistor in series with it.

 

[1946Zephyr]

Re: Big Twin starting problem

yep. the old 35.7 cube. Just about need a size 19 neck to pull one of them over for any length of time. May have to call in the Marines. Sounds like the compression on your motor is right up to snuff. They started puting compression releases on, in 1957, just because of that. Fortunately, I'm still young enough to hand crank one, but won't be for too much longer:redface:

 

[cougar1985]

Re: Big Twin starting problem

yep. the old 35.7 cube. Just about need a size 19 neck to pull one of them over for any length of time. May have to call in the Marines. Sounds like the compression on your motor is right up to snuff. They started puting compression releases on, in 1957, just because of that. Fortunately, I'm still young enough to hand crank one, but won't be for too much longer:redface:

hear ya on that one!my big twin 25 pulls over and starts on 1 or 2nd pull any more and im getting a good workout for sure,lol.my 1970 33hp is a bear also!

 

[tmcalavy]

Re: Big Twin starting problem

If there is a notch in the flywheel, pull the rope/recoil starter and use a rope in the flywheel notch wrapped around the flywheel...save your arm/shoulder, surgery sux.

 

[drmbykr]

Re: Big Twin starting problem

I found out it is a 28hp,I got SN# how can I get the year?
Starter solinoid is bad,can engine be started by jumping terminals like you can do on cars?

 

[F_R]

Re: Big Twin starting problem

I found out it is a 28hp,I got SN# how can I get the year?
Starter solinoid is bad,can engine be started by jumping terminals like you can do on cars?

1. So post the serial number already.
2. Yes.

2 1/2. That makes it a 12 volt. Disregard previous "advice".

 

[drmbykr]

Re: Big Twin starting problem

SN# is E02622.
thanks to everyone for their help!!!!!

 

[drmbykr]

Re: Big Twin starting problem

Sn# = E02622

 

[1946Zephyr]

Re: Big Twin starting problem

Model numbers for 28hps go as follows:

28202 1962
28302 1963
28402 1964
1965, they were upped to 33hp and this model went until 1970

 

[F_R]

Re: Big Twin starting problem

Model numbers for 28hps go as follows:

28202 1962
28302 1963
28402 1964
1965, they were upped to 33hp and this model went until 1970

drmbykr, Evinrude often runs the model number and serial number together. In this case it would be something like 28302-EO2622 for a 1963. It is the FIRST PART of the number that one needs to tell the year.

 

[drmbykr]

Re: Big Twin starting problem

thank you for your help.
now that we know it is a 1963 Evinrude Big Twin 28hp,does anyone know where I can get wiring diagram and engine parts diagram??