Today's solex maintenance ...

[SLOroadster]

Well, went out testing yesterday... Before doing that I took a close look at my jets and noted that the ends were different than the factory and some of my other after market jets (been getting them from CB Performance). They are supposed to have a "dish" and then the hole, but these don't have the dish in the tip, just the hole. Wasn't sure it would make any difference, but it does! The 170s were worse than the 165s, and I didn't even bother to try the 175s as they were the same. Looking as best I could down into the jet hole in the carb it looks like there is a corresponding "connection" area that may fit into the dish part of the jet (if it were there). I think these jets can be modified on a lathe or drill press, but what I also noticed is that ONE of the 165s I have is also wrong, and that may be throwing the readings on the wideband off because I don't think the mains are feeding fuel properly with the screwy jets. It may be that the 165 size is correct except for the fact one is bad, which irritates me since I just spent money on jets I may not need. I have a call into the company but in the mean time must now decide to either wait for proper ones if they have them, or go get these fixed. This makes my planned road trips difficult! Grrrrrr.

What a headache. Different style jets are no good. Look at it this way, at least you don't have some allen-head stop screws with holes drilled through the middle acting as your fuel jets. A few years back I sorted out a car down in Oakland that didn't run right. Guess what I found? Yeah, drilled out stop screws. It took me awhile to figure out what I was looking at. I pulled the jet blocks and was looking at them and then it dawned on me what I was looking at. I removed those, subtracted 30 from the air jets and installed a set of real fuel jets. You wouldn't believe how much better the car ran. After a little tuning the car ended up being one of the most well tuned cars I've done. Sadly I haven't seen the car in years.

Will

[Down under 311]

Greg ... At least you have identified the problem as annoying as it is ...
Reckon everyone who doesn't know what's in their cars to have a look...

Going to have to get a set of 60 idles from Tod I think as I still lean out slightly with light acceleration on either fuel mains... 155 or 160... Nothing pings just a slight hesitation...

[Gregs672000]

Sure is nice having a machinist for a close friend! Took my jets to Steve and a short time later they were properly modified to stock design. We also noted that per the jet drill kit he has the 170s were the same as the 165s, so we cleaned those up as well, even though I think the 165 is going to be right... We'll see today!

[Down under 311]

Well went out today to get a bit of a sound bite ... But alas the camera woman may not of been up to the task..





However I think I may of worked out my lean problem, back carb out of balance by about 1 full turn.. Smooth as now nice even exhaust... And idle back to 12.7 .. Reckon at upper end of mild acceleration before the pump kicks in the balance was causing a lack of fuel at said revs !! That's my theory and I'm sticking to it... Well until I go and test again..

Greg how was your morning ??

[Down under 311]

Ps click on the photo above for the video clip !

[notoptoy]

Sounds good, hope she didn't barf in or on the car!

[Down under 311]

'twas the wife so thankfully lunch stayed with her !

[Gregs672000]

'twas the wife so thankfully lunch stayed with her !

Ha, that was great! Love her laugh! Car sounds wonderful, sure wish mine was cooperating. I still can't get it to not go lean and stumble no matter what I do. Something just isn't right in transition, but if I fatten up the slow speed running system to compensate it runs in the low 12s in cruise and STILL goes lean, even with a big main jet. I know the pumps are working, but they don't seem to hit with a big enough squirt of fuel soon enough in the throttle progression. If I nail it is is pretty good, but with a softer pedal it drops in the high 14s or 15 (sometimes worse) and it's as though there is not enough vac to pull enough fuel from the mains. I pulled off the airbox and reved it up, looking inside the throats with a mirror, and everything is working right... It fact it sucked in so hard it almost pulled my mirror into the carb! I looked at the schematic of the carb and there are no other pump jets that control things other than the rod adjustment and the change in the pump jet size, no internal jet like on a Mikuni as I recall. I've tried my different main emulsion tube, tried running without the air box (I think it's quicker but a lot louder), richer and leaner idle emulsion tubes (changeable on the Dell) with different combos of jets... Still no joy. I have an idea of trying to increase the accelerator squirt a bit more, so we'll see... Damn, I want to take my car on a road trip, and while it is drivable it is not where I want it, and it frustrates me to no end!

[Down under 311]

Stupid question .... But mine were out of balance.. Causing it to lean out ... Have you got them balanced ? With trying everything else I had forgot the basics....?? The lean ness was exaggerated as one carb ran out of "go" before the other and stumbled on take off that it hadn't before

[Gregs672000]

OMFG, it has been a day. I spent the entire day trying to get this damn thing jetted right, and I just can't do it with what adjusters I have or the knowledge in my brain, not sure which. Since I'm the only one of us I know running 45 Dellortos, I don't know if it will all translate, but I'm sure you'll be able to relate...

Basically, I've tried every combination of jets and jet holders I have for the slow speed running system. I have two idle holders to try, one that is known to be lean, and the other known to be mid rich (the middle of the range of jet holders available). I've determined that this system operates the car to about 4000 to maybe 4500 rpm if I'm in say 3rd gear, maybe even 4th, and light on the throttle to stay out of the pumps. It will always run rich 12.4 below 3000rpms, then as it climbs it always goes lean, even to 17, often 15s and the car just stumbles, so at 4500 rpms it might be in the high 15s, way too lean. It makes no difference what main fuel jet i have in there, the stumble always occurs. And let's say I progress normally through the gears, if I press her even slightly it goes lean, yet i know the pumps are working at least a little. I have plenty of fuel on the top end if i bury it with most main fuel and air jet combinations I've tried, I just can't get the transition. I think it has something to do with what I think is a weak accelerator pump system, i need it to act more aggressively, but i am not sure i can adjust it to do so. The bigger pump nozzle has not really changed things (42 to 55). Only the rod is adjustable, but the last time i tried this the linkage started hanging up and holding the throats open for some reason. I know of no way to get the mains into the game earlier. The only other thing i can think of is to get an even richer idle holder and be able to find a jet that gives a good mix. It may be that what Dellorto meant by "richer" is in relation to how rich it stays in the upper rpms. This holder is really an air jet too, so I imagine that it, like a main air jet, controls the upper range of its function. Makes sense to me, but if that is the case I once again have to order parts out of england!
But my day was also so much fun due to unexpected break downs. One time, while out testing a few miles from my home (and tools) the car hiccuped while I was getting on it fairly hard to see what the mains were doing. It had gone super rich (10s) and it hiccuped. Then there was a tick tick sound, and she just doesn't want to go as hard now... So I shut her off and pull to the side. No carb issue. Start car... Tick tick tick! Off! After removing the valve cover using the only tool wide enough that I had, a mini palm size set of pliers... That was fun, I eventually determine that I lost a keeper off of #4 exhaust valve. Found the keeper, and by sheer luck found a small crescent wrench in the center console that would fit the lash adjuster, and praise God I got that sucker loose and reinstalled, eyeballing the lash and going looser than tighter just to get her home. Cell phone battery was dead, and it would take a tow forever and the rest of the day. So, get her home, adjust all the valves again just to be sure, and off we go to test again. A mile or so away and I'm getting on it just a little and *poink* something goes funny and we're back to three cylinders again...WTF! this time I brought some tools. Valve cover off, carbs checked... Nothin. Runs back home on three, tail between her legs. There I have my spark plug socket. Sure enough, number 4 is slammed shut. Hmmmm, what the hell caused that? These are new plugs but I made sure I got recessed noses due to those pistons. Bend it, gap it, we're back in business. Continued testing, still without success. Even went so far as to go back to the 37s, but I couldn't get those to work to my satisfaction either, so i put the 40s back in. And I've gone through at least 10 gallons of gas in 170 miles of testing.
So, right now I'm tired, frustrated, smelly, and a little bit high (gas fumes ). I have a few questions to post but am too tired to do it now. This is the time I remember that I've been here before and I will yet again conquer this challenge... Just not tonight!

[Down under 311]

Someone important once said without knowing the lows we don't really appreciate the highs... Unfortunately they never worked on duel carbs to come up with that one.... Good news is that this all happened whilst you were "working" not on a long run somewhere where a lot of say mg's (we don't like them here ) are standing arou d giving there 2c worth!!

I'm hoping the balancing of the carbs will largely cure my lean issues , as everything is spot on and soooo nice !!
Sending good karma your way.... Hope it works out...

[Skyman]

This is some great info guys. Greg, sorry to hear about your issues. It sounds like you almost had it where you wanted it a while back. I bet for most folks, your car would have been fine where it was at. I love the fact that you are as anal as I am and want to get it perfect. Good luck today getting it running. I'm hoping to have some time today to play with mine as well. Need to get the mid range above 11.0. I think going from the 175 main down to the 170 may do it. Haven't driven my car for a couple of weeks now due to vacation, work and weather. Rain is forecast for today. I'll try in between storms.

[Gregs672000]

So, I spent yet some more time on the car, but I think I've learned that I do not have the idle jet holder that my car requires. If you recall, they come in variations from lean to rich, and there are 10 of them to choose from. I have one that is 3rd leanest (a #9) and the new one (#1) which is right in the middle at position 5 (like so many carb n such companies, the numbers are not in order... That would make too much sense!). While researching whether it made any sense to see if I could adjust the accelerator system via the rod like on a Mikuni (I don't think I can in a manner that is going to help me as it turns out), I went looking for my Mikuni book. In it I found my Dellorto info that I had downloaded a long time ago. In the tuning section the author notes that idle holders in normal use are the numbers 1,6,2, and 8, all of which are richer in the scheme of things with the funky numbers they use. So, not only do i have only one of the most commonly used holders, it is also the leanest of the bunch. The author then gives an example using the next to richest one (a#2) where he suggests a 50 or 55 idle jet for a modified 2liter pinto motor on 36mm chokes. The smallest idle jet I have is a 55, but that doesn't work at all now because they all go lean... But as I think about it, if I was very careful the 55 gave me the best cruise ratio at 13.5 or so. Maybe that means that the "richer" idle holder does act as an air jet in the main system, and in essence I have too big an air jet for my slow speed system. When I try to compensate with a larger fuel jet it just messes that up but does not fix the over air issue... At least that is the theory I'm going with cause after that I don't know what to do! I've emailed my Dellorto guy in England with something to this effect and hope to hear back. If correct, then it's hurry up and wait for at least a week for more jets... So much for the Roadster road trip vacation, at least for the next few weeks.

I'm also a little worried about the motor. I did a compression test today, and the numbers were down across the board, some more than others. One and three were at 190, but two and four were at 180. Two gave the worst cold reading at 160, but came up when hot. What concerns me is that not long ago I tested and they were all very close and at 210. That's a big drop to me. However, I am not sure I used the same gauge and think my older but now broken one was of higher quality, so maybe that's it. I may do a leak down later, as this motor had as close to zero as you can get before with Total Seal rings... Really liked those. If there is any leaking that will tell me now. I also noted that number 4 throat was not pulling as much air as the other 3 on the meter, not bad but maybe just a bit more than I expected. I know some variation is normal, but with what happened yesterday with the flying keeper issue, and then the mysterious squished spark plug, one has to wonder. And my distributor seems kinda wonky. It has a lot of slop to it, like a lot of slop in the gears that mesh. It has very little advance in it by request, like 8 more degrees I think. I run a timing light on it and it advances, but it seems like the timing misses sometimes or jumps around per the flashing light... Not sure I can trust a cheap timing light to indicate all spark events, but I do wonder... Anybody else experience this?
Anyway, that's it. I stink like hydrocarbons again, and I'm starving... Damn car... I guess every relationship has it's rough spots...

[spl310]

Greg,

Have you tried the jetting program from Dave Andrews site:

http://www.dvandrews.co.uk/" onclick="window.open(this.href);return false;

It has some options and may get you close on the emulsion tube and jets

[Gregs672000]

Greg,

Have you tried the jetting program from Dave Andrews site:

http://www.dvandrews.co.uk/" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

It has some options and may get you close on the emulsion tube and jets

Yes, that is the info I have too. However, he is kinda inconsistent. When discussing idle holders he has you starting with a #2, but then on his lists of suggested jetting etc for both the 1.8 and 2liter pinto on 36-38 chokes he's using the #9 with a 65 idle jet? I sure can't run that, as when I use a 62 in the #9 my steady state ratio is in the low 12s ( no higher than 12.4) and above 3000 it climbs to 14.5-15.8, and any tap of the throttle and it leans 17-20! The other issue is that Dellorto made several changes to the progression system over the years, one of the things they are known for improving overall running vs other designs... If you can get it right! Some dells have 3, 4, 5 or in my case 6 progression holes, and I think they keep the mains out of the system until later vs other carbs. The only thing I can think of doing is going richer on my idle holder with the idea that this will help control ratio at 3000-4500 better (just like an air corrector jet does for the mains) while finding a idle fuel jet that isn't over fueling at lower rpms. Unfortunately the state side supplier does not stock idle holders (and some of their jets were questionably made anyway) so i have to go overseas which can take longer and is more expensive. Then again my contact there, Matt, has been very helpful so I don't mind sending him some business... I just want my damn car to work right. It teased me and now I want more!