Mcculloch Ingition testing

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pafire

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Recently acquired an old 1-42 Mcculloch and has no spark at the plug (replaced with a new one). After searching the forum I was unable to find the steps used to check out the points, condenser, and coil on this saw. Does anyone have the preferred readings for the condenser and the coil.
 
Go to the “Beg for manuals” thread & ask for a service manual. If Ray does not have one, you can download one for $5 from chainsawr.com.

What’s most important is to make sure the points contacts are clean and that the condenser & coil windings are neither shorted nor open. I’ll bet the old points are corroded up.

Drawing info from other old saws (never worked on a 1961 vintage Mac), the cap should read about 0.2 microf, then 0.018” on the points gap & about 1.4/7.5K ohms on the respective primary/secondary coil circuits.

2814F1BD-7585-4E73-B0F1-344B89F74679.jpeg
 
Instead of sandpaper etc, you can get an actual points file at Napa for pretty cheap, and it's good quality, I think I paid less than $10. So you can do a good job cleaning up the points and keeping them flat and even with each other.
 
Instead of sandpaper etc, you can get an actual points file at Napa for pretty cheap, and it's good quality, I think I paid less than $10. So you can do a good job cleaning up the points and keeping them flat and even with each other.
Clean the points FIRST - simplest thing and more than likely the problem. I have replaced one coil on the 20+ vintage saws I've restored. Good to know about the file. I have used points files for 40+ years - didn't know the still made them. Points surfaces need to be shiny and smooth. Sandpaper can leave peaks and valleys that burn quickly. If you must use sandpaper, use 400 or finer and spray with contact cleaner to remove any residue left from the sandpaper.
 
A good place to start is to clean and regap the points to proper specs.

Sent from my SM-S367VL using Tapatalk
 
Yep....most of my old saws use points so when i researched cleaning them I found out about points files. I got this one at Napa for about $8 i think, and it works nice.
 

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Thanks hotshot for your info on the corroded points. On to the next problem of the recommended minor or major carb repair kit for this saw. After bringing up this model on the acresinternet site, it only listed tillotson HL series. Are many of the repair kits of a general nature or do I need a carb spec for the HL 87c that is stamped on the carb body.
 
Go to the “Beg for manuals” thread & ask for a service manual. If Ray does not have one, you can download one for $5 from chainsawr.com.

What’s most important is to make sure the points contacts are clean and that the condenser & coil windings are neither shorted nor open. I’ll bet the old points are corroded up.

Drawing info from other old saws (never worked on a 1961 vintage Mac), the cap should read about 0.2 microf, then 0.018” on the points gap & about 1.4/7.5K ohms on the respective primary/secondary coil circuits.

View attachment 839484
Sent @pafire an ipl, owners manual, service manual and service manual supplement
 
That 87c carb shows up in the HL vintage section on Tillys website, but the referenced carb kit RK-404 is NLA of course.

I’d call VE Petersen in Ohio at (419) 838-5911, and maybe they could recommend a modern kit that has the same gaskets, needle, & seat as yours.

Tilly made thousands & thousands of those HL carbs over the years, and then combined a lot kits into a fewer number of universal kits, so you may get lucky.
 
Just some Mac info about your saw. You can also get some info in the chainsaw stickies section about Mac's. A guy by the name of heimannam has good info about mac's. When he talks to you, listen up.

The points should be gapped at .018-.020. The condenser is .18-.22UF
The coil primary should be in vicinity of .025 ohms-1.5 ohms on the primary and 3.5-7.2K ohms on the secondary. Most generally when they are not firing the points are the problem. Make sure the kill switch is not on all time. You can remove it's wire to see if you then get fire. Coil air gap is .008-.012. (typically .010)Mac made a special tool at one time for setting the timing by the points gap, but it's not necessary and NLA. If the points are not making contact on you tester 1st try just dragging a clean white paper through them while they are closed and then re-test contact. If not go try a points file but filing old points is in the same category as peeing into the wind. I've found new points by doing a saved search on flea bay very reasonable, like $8-10.
You can test the condenser using a DMM. Condensers are kinda pricy. You can find some parts or reference to interchangeable parts a chainswyer.com. Watch out for the word KART engine and vintage. They use these words to jack up the price.
You can find a carb kit for around $15 and you can use a RK88HL kit on that 87D carb. Watch out and try to save the little cork gasket (leave it in place) when you remove the bottom metal because most generally the new kits have the wrong size cork gasket. Also be careful with the sintered iron carb filter and it needs cleaned with air pressure. They clog and you cannot see such by eyeball.(close but not cigar) No need in flogging the carb until you get it firing. After getting fire you should prime into the carb throat and get a promise to run by ties the throttle wide open. They always like to start with full throttle. (it's their nature for such) They need good compression to get a run promise, at very least 125 and up, 150 is good and checked with a reliable small engine comp tester, not a auto tester. You will probably have to replace the fuel line and the little clamp on the carb barb needs to be replaced with a small clamp that can be tightened. If you are seeing any gas in the air box when testing you have a fuel leak and she won't go good.
That 87D carb can be replaced with a Tillotson HL63D, E or A, direct fit no mods required..
The 63 carb has a spring loaded choke butterfly (spring loaded open) and yours don't have the choke butterfly. The HL63 uses the same RK88HL kit.
I've bought both carbs on flea bay for around $15-20.
I have some tips for starting them saws when they are cold that saves lots of cranking, blistered fingers and sore shoulders.
Them old heavy saws were not made for Nancy's and Pansies to operate.

Here is some carb info. GOOD LUCK TO YOU.
Some of them saws also came out with a carb made by Mac and some had one termed Bullfrog carb. You do not want those carbs. Make sure the gas tank is clean and the in tank filter is good.

McCulloch chainsaw carbs types



If you are asking about Carbs for the old Mac saws here is what I've used and will interchange, from my Mac notes.



The Tillotson HL63D, E, and A can be used interchangeable and use same kit (RK88HL)and can also be used in place of the 87D, but the 87 D cannot be used to replace the 63A, D, E,

because the 87D does not have a choke butterfly inside the carb. (the choke assembly for the 87D carb is made on the saw air box)



And these Tillotson carbs can be used to replace the carbs that were made by McCulloch but a throttle linkage kit will be needed.

I seen some mod carb kits at chainsawyr.com every once in awhile for the old 1-40, 1-50, 250 series of Mac saws.



The 1-40, 1-50 series of Mac's came out with approx 3 different types of carb's during their production, a HL87D, HL63A, D, and E and a carb made by McCulloch and I think

I’ve heard of some Mac 250’s that use a Tillotson HL63F carb which uses a RK106 kit.

maybe one type of carb referred to as a Bullfrog carb.(it's bottom looks like a bullfrog belly)The Tillotson carbs will bolt up and replace the Mac, bullfrog and flat back carbs with correct linkages.



The Tillotson carbs are user friendly to repair and service info and parts lists readily available at the Tillotson website, look at HL series carb.





The kit for the Tillotson is a RK-88HL at about $10 from flea bay
 
Keep a heads up when re-installing them carb's because you can easily break a ear off the engine side of the carb or the manifold or other things if the manifold adapter is not lined up properly when you start tightening the bolts/nuts. The carb manifold adapter has a little lip on it that if not aligned will cause such.
 
Also about your carb:
Take a look at this pic on flea bay and note the stud in the top of the carb that holds the air filter and it's top.
It's a 5/16 fine thread, it must be snug in the top of the carb to seal. You can take a bolt/stud of proper size and drill a small hole thru for connection of a low pressure gauge and with about 10-15 pulls of the starter rope with a tank of gas you should see a pressure buildup of around 1/2- pound or little more of pressure. this indicates that the carb's fuel pump is operating. If not ever any pressure you are SOL for a run. Carb probably needs at least a pump diaphragm or kit. I have dumped a little bit of mixed gas into that stud hole and let the rig set for couple days to soften the pump gasket and get a pressure and a run.
Most generally if you get a fuel pressure the carb is probably ok.
Start out with the jets on the carb at about 1 turn and the L jet can vary from 1/2 to 1 1/2 out. Make sure you keep both jets as far out so as to make the saw run rich. You can use 50:1 mix now days instead the more oil mix.
When trying to start cold tie the throttle wide open by wrapping a #10 solid copper wire around the throttle and when the saw starts just slide it down off the trigger and leave it in place.
If you get er going good if it has the cast muffler you can just prime the saw through the muffler and not have to remove the air filter and it's cover.
This is a clean looking carb like yours but most likely needs a kit. Them dogs are older than me.
I've bought NLA vintage HL63's and 87's new old stock in the box from flea bay for $20.
You can finds lots of info at the Tillotson website about kitting, etc.

Good Luck to you.

https://www.ebay.com/itm/USED-TILLO...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649
 
I sent this info to you in a PM and thought maybe someone on here might be interested in this real good link to Mac service info. they also have other Models of Mac service info priced dirt cheap and other makes of saws info and is also a good place to kinda check out going prices for vintage parts.
I just happened to be into my Mac stuff in the shop awhile ago throwing a parts carb into the stuff and I had see where I made a note that the tygon tubing that I used on the 1-40 series is 3/16 ID x 1/4 OD.
AND chainsawr has a really good McCulloch Service Manual that is the real deal for about $5 at this link.
https://store.chainsawr.com/product...and-repair-manual?_pos=1&_sid=59f7ba63c&_ss=r
They send it to your email as a download pdf and I placed it onto DVD/RW disks and also SD card (flash drives) so as if the computer crashed I would have copies.
It's really a good service manual for the 1-40- 1-50 maybe the 250 saws and was the Mac service shop manual. Really good SERVICE info. Lots of pages of assmebly/dissembly, carbs, recoils you name it it's in this pdf.
 

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