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Discussion Starter #1,541
It's a different engine. If you want to know the benefits of that gizmo, talk to an engine builder who specializes in race engines. IMHO, it's overkill for a street engine. Yours is going to be stock, so it's even less necessary.
You may just be right. I'd still like to know the difference in slack between a new chain and a used one. I want to measure mine to see if it's way out of the "correct" size.
 

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My dad was a Machinist/Tool and Die... he showed me how to look for wear. The new chains show less flex/play/slack/droop than the used. Don't remember the brand of the chain we bought.
 

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Can't remember if I've seen it here but there's a mod using mini parts (as far as I remember) to recreate the Alfaholics part.
I recognise it from a Renault 12.
I think there are thousands (ok many) of engines with this


There was also a mod that replaced the chain with gears, not sure how successful that was
https://www.alfabb.com/bb/forums/alfa-romeo-parts-sale-wanted/635473-os-giken-gear-gear-oil-pump-drive.html


I only mentioned them as a bit of lower chain trivia, history etc ;)
 

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Discussion Starter #1,544 (Edited)
.... Don't remember the brand of the chain we bought.
I see quite a range in prices on these...from CA at BP 9.0 (made in India Rolon brand)... to OKP at EURO 42.00 (IWIS brand made in Germany). I'm thinking that if the cheap ones are made in India with the usual inferior materials (and questionable Quality control)...they won't last so long anyways....in which case the original one I have now may be just as good a couple of years from now. Or, I go for the better (presumably) German made one...but it'll probably end up costing me $120.00 (all in).
 

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Hopefully the German ones don't originate in India ... 🙂
Pete
 

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I am going to use a rotisserie To be able to access all areas so to speak. I will attach the front to the engine mountings but where to attach the back? There is no boot floor and the rear chassis legs are shot. Anybody ever done this ?
 

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Discussion Starter #1,550
... but where to attach the back? There is no boot floor and the rear chassis legs are shot. Anybody ever done this ?
You mean both supports are completely gone up to the spring pans and the T-bar mounting points? If not, the photo below shows how I built the rear tilter frame.

IMG_0403.jpg
 

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Yes, both chassis members will have to be replaced along with the floor pan under the rear seats. I was thinking of having the frame attached to the engine mtgs at the frone ang going upwards and the rear one coming out of the boot and upwards and the two linked by a bar going through the front and rear wingow aperture. Do you know if these parts are available as they are not listed anywhere I can find... excuse the spelling, Albanian keyboard..
 

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Discussion Starter #1,552
Yes, both chassis members will have to be replaced along with the floor pan under the rear seats. I was thinking of having the frame attached to the engine mtgs at the frone ang going upwards and the rear one coming out of the boot and upwards and the two linked by a bar going through the front and rear wingow aperture. Do you know if these parts are available as they are not listed anywhere I can find... excuse the spelling, Albanian keyboard..
I have never seen these parts available as NOS loose items. I have seen a NOS complete front clip for sale a few years ago....but that's about it. The boot floor and reinforcing bracket for the rear axle strap mounting point are available from Classic Alfa. Sounds to me that you need to source a good complete rear end sub chassis from a donor vehicle. I would contact Classic Alfa....they might be able to help you locate such parts....they've been breaking out cars for years for their own projects......worth a try.
 

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Discussion Starter #1,554 (Edited)
Lower Timing Chain Slack

Finally....after a 2 week vacation break (comprising a 7 day Rhine river cruise..followed by a three day stay in Amsterdam)....then starting a new job....I was finally able to get back to business. New lower timing chain arrived today and after fitting it...I finally have an answer to the question..."how much slack is in a new chain?". The photos show the old ....with slack (or droop) of 0.231" (5.9 mm) from straight...versus the new with a slack of 0.105" (2.7mm). Is this that critical when all is said and done? maybe not so much on this completely mild engine rebuild.
 

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The primary need is to have a tight enough chain that it will not skip a tooth if the engine backfires. Your old chain looks close to that limit, and the new one looks solid. Any tighter chain will probably just increase wear.

Robert
 

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Discussion Starter #1,556 (Edited)
Getting back to the engine build....the best I could do w.r.t. to achieving the allowable pinch at the connecting rod big end bearing caps was around .002"-.00175". The factory specs recommend between .0009"-.0025" and although I'm at the upper end of the range....I don't think I need to go any tighter than this. To do so I would have to wet grind down the big end cap surfaces .....which is not something I really want to mess with at this stage. Plus the wear limit according to the factory specs is .005" ...which sure seemed high doesn't it?
 

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Discussion Starter #1,557
Today was a set aside so as to complete the assembly of the bottom end on the engine. I managed to install the main caps, lower timing chain and front cover...and a few of the ancillaries....

20190810_184033.jpg

When I got to the pistons and liners....I could not find the liner o rings and wrist pin clips..!!!!....arghhhh!!!!....:cursing:....I always left these in the box that the pistons came in....but they weren't there. I spent over an hour scouring every inch of my garage...:cursing:.....and all the boxes...but to no avail!....:cursing: Then it dawned on me.....I brought that box with the pistons to the balancing shop didn't I?....yes I did, and this was the first time I opened the box up. So what's the likely hood that the shop didn't just toss them out?

Monday first thing I'm going to give them a call ....I hope lady luck is on my side. Should that not be the case....I see that the o rings are available from most of the suppliers....but no one lists wrist pin circlips. I suppose I could use the original ones.....but I already reassembled all the spare parts into an engine and I'd rather not have to dig that out and take it apart again.

Does anyone know where I can get these? Pistons are Borgos.
 

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Discussion Starter #1,559
Well as it turned out...the balancing shop did not have the circlips in their possession....and as so often happens with misplaced items....sometimes you just need to take a break and resume the search...and sure enough a few days later....I find the dang things right there in the corner of my work bench!

20190812_163236.jpg

The liner o-rings however were nowhere to be found....so a quick call to Classic Alfa...was needed to order a new set (with a spare for good measure). I believe this time they came in record time..4 days amazingly. That allowed me to finally complete the installation of the liners, pistons, connecting rods and oil pump.

IMG_4559.jpg

..and for good measure I threw on the alternator.....I'm finally starting to see the light at the end of the tunnel on this engine build...especially since the cylinder head is all ready to be re-assembled....(pics to follow)...:grin2:

IMG_4554.jpg
 
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