Spider 1750 engine; cyl. wall question - Alfa Romeo Bulletin Board & Forums
 1Likes
  • 1 Post By evieceli
 
LinkBack Thread Tools Display Modes
post #1 of 9 (permalink) Old 05-31-2019, 10:23 AM Thread Starter
Registered User
 
evieceli's Avatar
 
Join Date: Feb 2017
Location: Las Vegas, NV
Posts: 79
Garage
Spider 1750 engine; cyl. wall question

Hello everyone,

I have a 71 Alfa Spider with a 1750 engine that only has 16380 miles on it. It's been sitting abandoned since 1992 (the last time it was running) and although was covered, humidity got into it slightly. There isn't bad rust except for tiny spots in cyl #2. Before I stopped running the car, I had just changed the oil and had fresh antifreeze in it so fortunately for me, its still very clean. Water jacket is pristine, engine turns very easy/freely.

My dad has since decided to restore the car's body and I am glad that he did. Now I am continuing the restoration project on my own as he is now deceased. I have a deep sentimental attachment to this car so I truly want everything done right. My question to you all is if I should replace the pistons/sleeves/rings/bearings.... or if you think what I have now is salvageable or ok to use as is?

I cleaned the valves but they need to be lapped as they all leak. I individually tested each by simply closing both valves and placing a spark plug to close the hole... then added a puddle of water and proceeded to blow compressed air into the intake and exhaust ports. Every valve leaked / bubbled. I remember this car having very high compression (great oil pressure) when it last ran back in the 90's yet when I recently did a leak down test, I heard air hissing out of each side though nothing out of the bottom end (listened from the oil dipstick hole) so most likely the rings are still good. I could be wrong..., hence my inquiry to you.

Here are some photos of it for your evaluation. The two pics of the cylinder are from both directions (not the same photo twice)
Attached Images
   
evieceli is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 05-31-2019, 12:25 PM
Moderator
Platinum SubscriberModerator
 
Alfajay's Avatar
 
Join Date: Jan 2005
Location: San Juan Capistrano
Posts: 9,631
It's easy for me to spend your money, but...

If I were doing it, I would completely disassemble the engine and at least inspect the liners, rings, bearings, crankshaft, camshafts, followers, oil pump, .... I can definitely see pitting/corrosion where the rings sat against the liners during storage. Whether that is shallow enough to come out with honing, or whether the liners are shot is tough to say just from looking at photos.

The bearings / crankshaft, cams / followers may have similar corrosion damage. Without disassembling and inspecting them, it's tough to say. That fact that the engine had good oil pressure 30 years ago is nice, but doesn't mean much today.

Jay Mackro
San Juan Capistrano, CA

'63 Guilia spider
'65 Guilia Sprint GT
'67 Duetto
'91 164L
Alfajay is online now  
post #3 of 9 (permalink) Old 05-31-2019, 01:10 PM
Registered User
 
goats's Avatar
 
Join Date: Jul 2006
Location: san diego CA
Posts: 4,999
I agree with Jay. I'd be really hesitant about not doing a full teardown to see what the condition of everything is. You will for sure want to replace the cigarette seals and I think if it were me I;d want to know how the crank journals look. Take you time this work is not difficult, its just precise.

74 GTV with 10548's and Ingram pump
71 Spider 1750 BOMBER ; 1995 LS 78K tight fast car
goats is online now  
Sponsored Links
Advertisement
 
post #4 of 9 (permalink) Old 05-31-2019, 08:24 PM Thread Starter
Registered User
 
evieceli's Avatar
 
Join Date: Feb 2017
Location: Las Vegas, NV
Posts: 79
Garage
Thanks everyone for your insight on this. I agree with you and will go ahead and take the rest apart. It's not as if there's much more to do, especially since the engine is out of the car and on an engine stand. There's really no excuse for me not to check everything out.

On another thought (related to this still of course...), If I buy a complete overhaul kit from Spruell Motorsports, I noticed that they have high compression pistons with liners. I recently had Wes Ingram restore my fuel injection pump. He asked me before he rebuilt it if I wanted to make it a performance pump. I replied that I'm keeping things stock. I'm wondering if that was a bad idea? If I go with the Spruell Motorsports kit found here:
Alfa Romeo parts from Spruell Motorsport Alfa

Do you recommend that I use the 9.5:1, 10.5:1 or 11.5:1 ratio option? Does 10.5:1 still allow the use of regular unleaded? I might as well do this right. I don't want to take it apart again once it's done. Sorry for yet more questions.

Last edited by evieceli; 05-31-2019 at 08:28 PM. Reason: corrected a grammatical error
evieceli is offline  
post #5 of 9 (permalink) Old 05-31-2019, 09:53 PM
Moderator
Platinum SubscriberModerator
 
Alfajay's Avatar
 
Join Date: Jan 2005
Location: San Juan Capistrano
Posts: 9,631
Quote:
Originally Posted by evieceli View Post
Do you recommend that I use the 9.5:1, 10.5:1 or 11.5:1 ratio option? Does 10.5:1 still allow the use of regular unleaded?
I'm no authority, but my sense is that 10.5:1 would work with premium fuel. 11.5 is pretty high for street use. Keep in mind that compression ratios will vary based on how many times the head has been milled, though if this engine really has only 16,000 miles, it's head is probably still its original thickness.

Jay Mackro
San Juan Capistrano, CA

'63 Guilia spider
'65 Guilia Sprint GT
'67 Duetto
'91 164L
Alfajay is online now  
post #6 of 9 (permalink) Old 05-31-2019, 10:11 PM
Registered User
 
goats's Avatar
 
Join Date: Jul 2006
Location: san diego CA
Posts: 4,999
My advice would be to stick to lower compression. Unless you are racing it around, it will be fast enough for normal use. Especially since you have stock fuel injection.

I am sure you will get the entire spectrum of advice here!

74 GTV with 10548's and Ingram pump
71 Spider 1750 BOMBER ; 1995 LS 78K tight fast car
goats is online now  
post #7 of 9 (permalink) Old 05-31-2019, 10:22 PM Thread Starter
Registered User
 
evieceli's Avatar
 
Join Date: Feb 2017
Location: Las Vegas, NV
Posts: 79
Garage
Yeah, I value your advice. Keeping things simple is pure bliss sometimes. I restored a 59 corvette.... didn't keep things so simple. What a cluster that all became. LOL You'd think I would had learned my lesson.

I've decided to go with Spruell Motorsport's standard kit (9.5:1) for $999 which has everything I really need aside of some gaskets that I have to purchase separately such as the two throttle body gaskets of the intake. I remember driving that car when it ran. It had plenty of power and was very fun to drive around. I'm kind of embarrassed in stating this but even though I've worked on Alfa's since I was a teenager (I'm 50 now), I never noticed or changed cigarette seals. Hmmm... going to look that up.
evieceli is offline  
post #8 of 9 (permalink) Old 06-01-2019, 12:25 AM
Registered User
 
spydaman's Avatar
 
Join Date: Oct 2010
Location: Brisbane Qld. Aust.
Posts: 679
Garage
Hi mate good luck with your project .You know not many cam tail spiders came with a 1750 engine . Not sure of the number, but I think they were produced in 1970 and uprated to 2000 in the first half of 1972. I could be wrong but I think you have a pretty rare car if it is the original engine. Regards John

Current cars 1975 spyder under resto, 1973 Berlina Resto 1976 Berlina parts car 1972 GTjunior fully restored, 1 complete rolling shell spyder.exit 1989 75 T/S sold
spydaman is offline  
post #9 of 9 (permalink) Old 06-02-2019, 10:08 PM Thread Starter
Registered User
 
evieceli's Avatar
 
Join Date: Feb 2017
Location: Las Vegas, NV
Posts: 79
Garage
Thanks John... I was told that in 1971 the 1750 engines were being phased out and replaced with the 2000 ones. So I have an earlier one and am glad that I do. Luckily I have a second 1750 engine but haven't taken it apart to see if it turns free or not. Regardless, I'll most likely fix that engine as well.
spydaman likes this.
evieceli is offline  
Reply

Tags
cylinder sleeve, piston liner, valves

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Alfa Romeo Bulletin Board & Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome