Hello to all...I am looking for some good manuals/articles on the set-up, care and maintenance of my Dellorto DRLA 45's. Can't seem to find any manuals available. Also, what is the difference between the DRLA and DHLA models?......Thanks
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Dellorto Tech Book by Bob Thomlinson:
https://www.cbperformance.com/product-p/0101.htm
I always thought that a DRLA stood up and a DHLA lays down. Different orientations.
So a DRLA would be a "Downdraft" and a DHLA would be a "Sidedraft".
Well there ya go.....another piece of information to be stowed away....Thanks for the info....Larry
Just to cornfuse things even more, my Dad's Ford Furgeson farm tractor had a Stromberg "Updraft" carburetor that did exactly that.
@Gordon Nichols posted:Dellorto Tech Book by Bob Thomlinson:
Unfortunately, out of print and unobtainium. .
Back when I had a nasty flat spot on my Moto Guzzi Monza I bought this book to sort it out.
https://www.dellortoshop.com/c...arburetor_Books.html
It’s about their motorcycle carbs, but it unlocked the previous black magic voodoo of carburetion for me. The DRLAs were relatively easy to understand once I understood how a carburetor works.
Spoiler Alert: Carbs suck and FI blows.
eta: There’s also a good bit of DHLA info on the interwebs due to their popularity on Brit 4 cylinders. Pretty much everything transfers.
@dlearl476 posted:Unfortunately, out of print and unobtainium. .
Back when I had a nasty flat spot on my Moto Guzzi Monza I bought this book to sort it out.
https://www.dellortoshop.com/c...arburetor_Books.htmlIt’s about their motorcycle carbs, but it unlocked the previous black magic voodoo of carburetion for me. The DRLAs were relatively easy to understand once I understood how a carburetor works.
Spoiler Alert: Carbs suck and FI blows.
eta: There’s also a good bit of DHLA info on the interwebs due to their popularity on Brit 4 cylinders. Pretty much everything transfers.
Great.....Thanks
Ok, so that link sucked so try this one for rebuild info:
https://www.dellortoshop.com/c...lorto_downloads.html
There are a couple of shops in Europe that are great for Dell parts and info and if you search around on Google for all things Dellorto you’ll probably find not only parts but all the info you’ll need to keep yours healthy.
Yeah, a LOT of parts interchange between DHLA and DRLA, just like Weber IDF and DCOE also.
And for the record, @dlearl476, carbs suck, and EFI squirts....
@Gordon Nichols posted:Ok, so that link sucked so try this one for rebuild info:
https://www.dellortoshop.com/c...lorto_downloads.html
There are a couple of shops in Europe that are great for Dell parts and info and if you search around on Google for all things Dellorto you’ll probably find not only parts but all the info you’ll need to keep yours healthy.
Dellorto shop is great. I generally get my orders from them in <10 days.
But I’m still kicking myself that I didn’t buy Tomlinson’s book, back when it was available. Or from CB.
I’ve got both of Thomlinson’s books - Weber and Dells. I’ve had the Dellorto book for 20 years and got the Weber one years back when it was available. Some folks on here don’t care for Thomlinson’s books, but for me doing a rebuild or adjustments, they seem to be OK.
But then, I’ve got some experience rebuilding carbs over the years, although mostly American V8 versions (GM 350 or Ford 351) or Mikunis on snowmobiles or the occasional chainsaw or lawnmower….. As long as you don’t lose the Black Magic Jou-Jou in them, Carbs work pretty well.
Harneys Carb clinic goes into detail rebuilding and setting up Webers. I couldn't find them online, but they've been posted here in the "paying" section.
I can rebuild either Webers or Dells. I clean them in my ultrasonic tank. Really they aren't that difficult, just careful cleaning and assembly. Set up your work area and make it SPOTLESS. I use Simple Green, water, compressed air and spray carb cleaner. I change the cleaner in the tank for each carb. Use some brass and nylon brushes and a few screwdrivers and wrenches. After cleaning, blowing out and carb cleaner blasts I set the carbs in the sun. I put the small parts in CLEAN plastic bins. Make sure the screwdrivers fit EXACTLY into the slots, no slop. This way is doesn't look like a hack did the work. Use NEW rebuild kits from a reputable seller.
The most important thing is EXACT float height, make sure both carbs are identical for the top and the drop. Use NEW float valves. Weigh your floats, make sure they are the same(and not gas-logged). And fuel pressure: not more than 3.5 psi for Webers or Dells.
After float height, the same throttle stop setting on both carbs is key. Once the engine is running the stops will be set with a "snail". Also making sure all the jets are clean and the same size, and all "mixture"(they're actually idle mixture VOLUME screws, the mixture is set by the jet size) screws set to the same turns off lightly closed(1.5 Weber, 2.5 Dell).
Here's the Harney article that (I think) Terry Nuckles posted some time ago. I know it's for Webers, but much of the background info applies to ANY carburetor and it's super well written.
Hello to all of you who have contributed/responded to my query on the Dellorto Carburetors....now I need to settle down and do some reading .....Thanks Again!!!
Larry:
DannyP rebuilt my dual Dell 40's and they are perfect.
I have the Thomlinson book. I would be happy to scan some of it and email to you if you can let me know what info you are looking for.
Thanks....it was the one book that I was able to order, should be arriving tomorrow (if you believe what they say) appreciate the offer.....
@Larry Scislowicz posted:Thanks....it was the one book that I was able to order, should be arriving tomorrow (if you believe what they say) appreciate the offer.....
Where were you able to obtain it? Guys are always looking for it.
The book that I purchase was not the Thomlinson book. This is the ONLY Book that I was able to find, got it from Carburetors Unlimited.com. Let me look through it and if need some info that is not in there I'll get in touch and see if it is in your book. Appreciate the offer.....Larry
Don't know why CB doesn't sell digital copies of the Tomlinson book. Hard copy printing is expensive to produce and inventory, but discs, thumb drives, or online downloads are pretty cheap.
The problem is once it's digitally out there, even though it's way cheaper(zero cost basically) for them to sell, they'll sell less.
It would be cool to have the book available online as a download though.
@DannyP posted:The problem is once it's digitally out there, even though it's way cheaper(zero cost basically) for them to sell, they'll sell less.
"Sell less"? Am I correct they are selling zero now? If so, scanning the manual to digital doesn't sound like much of a sales/marketing risk. Even if they actually gave it away for free with a link on their website it would provide more sales/marketing value as 'good will' than the zero sales return their asset is providing now.
It seems to me that whether you sell in print or digital, the pirating risk is the same. Print copies can be scanned by anyone, same as copying digital files.
There could be a reasonable motive to intentionally stop circulation of the book. If there is a decision to stop commercially supporting the (obsolete) Dellorto product, there is no reason to provide a technical resource perpetuating support.
I'm not going to second-guess CB. They're the best at what they do. I can say for fact; I loved the heck out of my Tomlinson Dellorto book!
@RS-60 mark posted:I can say for fact; I loved the heck out of my Tomlinson Dellorto book!
I'm really glad to hear that somebody found some value in this book.
I've owned my copy for more than 20 years and from Day 1 found it to be pretty much useless to me for troubleshooting, setting up, jetting, or rebuilding the carbs. I can't tell you the amount of time I spent (as a young man, getting rapidly old) reading, rereading, taking the book into the garage, thumbing through it looking for a clue (any clue, really) in a vain effort to point me to my problem. The book never helped. I eventually learned my way around a set of Dellortos, but it was 100% the result of tearing the carbs apart and staring at them, then going in and reading everything I could on TheSamba.
There is good information for quite nearly everything out on the internet, and there's a ton of misinformation as well. It takes a bit to sort the wheat from the chaff (there's a 140+ page thread over on TheSamba filled with gems and folklore both in equal measure), but there are people who understand this stuff. You need to find those guys.
Perhaps Mr. Tomlinson was one of the smart guys, but I've never been satisfied with advice like "Don't worry about your air-correction jets. Everybody just uses 180s". I want to know what those jets actually DO (ask 50 different guys. You'll get 25 different answers and 25 "I don't know"s). Before purchasing, I was hopeful that a book touted as the Dellorto Bible would offer a plausible explanation for the "mysteries". I was left wanting.
I've never known how much to weigh in on threads like this because there's always such a love-in for the Tomlinson books (the Weber book is equally useless to me) that I've wondered if perhaps it was just me. But I've talked with enough other people who found the same thing to be reasonably sure it's not. It's a lot more rare to find somebody who's been able to glean something.
Back when Mark Harney was posting on TheSamba, I was able to get more information in one of his posts than in the entirety of the Tomlinson Bibles. The information on Webers all transfers over to Dellorotos, because they are essentially the same carbs with a different idle jet location. The principles all transfer.
My car is tuned really, really well. I thought it was perfect before I drove @DannyP's car and came to the realization that there's more to learn, and more to gain in the tuning (of which, ignition is 75%). Most cars aren't even close.
This is my experience. Obviously, RS-60 Mark had a different experience. Your mileage may vary.
I'd happily sell my copy, assuming I can find it.
Yeah, I was a bit unhappy when Mark Harney disappeared.
Ditto that, Michael.
And @Stan Galat I'm totally in agreement about the CB/Tomlinson books. John Connolly really knows his way around Webers and I learned quite a lot reading his comments on thesamba.com. Mark Harney was a treasure to learn from as well. There are a lot of good older carb setup threads that both men commented on.
Honestly, four things are needed: cleanliness of carbs, absolutely equal air and fuel(carb setup), precise and maximum spark, and a wideband O2 sensor.
But reading what the sensor is telling you is the harder part.
Modok (Glen Urban) and Alstrup (Torben Alstrup) are guys worth listening to.
And yes, when I got a wideband was really when the world opened up for me.
You could start your search on the Samba here, and then branch out. TONS of info on there but you'll probably need to start a (free) account to get into the forums.
@Gordon Nichols posted:You could start your search on the Samba here, and then branch out. TONS of info on there but you'll probably need to start a (free) account to get into the forums.
Hi Gordon....yes, I stumbled on this site the other day and have been going through it, lots of good information. Have to do some data mining on it!....
