 1.7 Rebuild First Start Up Advice, 1.7 Start Up on stand |
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| Robroe |
 Jul 4 2024, 05:15 PM
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#1
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Member  Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest  |
Have 73 1.7 bought in pieces. Engine has been rebuilt and ‘souped up’ however I don’t know what internals were installed. New crank, cam, pistons, rods and heads. but I don’t know which ones. Weber 44 idf carbs. Never had oil in it and been stored unstarted for 10 yrs in climate control. I’ve added oil by slow dripping 2 quarts through the oil pressure sensor hole. Oil dripped out of the rockers so I’m pretty sure it got some oil as pre lube. It’s on a home built test stand with the transmission mounted with the starter.
I’m trying to turn the engine over by hand with the plugs out. Have squirted oil in each plug hole. I’m able to turn the engine by hand about 45 degrees and it gets harder to spin so can’t go any further. Would it be a good idea to pull the rocker arms to see if the builder installed some wild cam without checking valve/piston clearance? It doesn’t feel like internals are hitting each other but who knows? Would hate to pull the heads if I don’t have to. Any thoughts before I break something? Rob Roe Newbie |
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Replies
| technicalninja |
Jul 13 2024, 10:26 AM
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#2
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Advanced Member Group: Members Posts: 2,531 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region 
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On balancing...
Pistons/rods I will balance to +/- 0.5 grams But the entire assembly I will accept +/- 2 grams. Doesn't have to be super close! When an engine runs it ends up with oil entrained on all of the parts and this oil "ropes" differently on different parts. Due to the amount of oil hanging on the parts the engine will NEVER be in "perfect balance". It CANNOT happen unless you get rid of the oil! Dry sump has less of this happening but it's still significant. When someone tells me the entire assembly is +/- some tiny amount it just means that they don't understand what is happening inside an engine while it's running... When a good machine shop calculates "bob weights" for a V engine they should ALWAYS include 5 grams for this entrained oil in each bob weight. |
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| Robroe |
Jul 13 2024, 02:11 PM
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#3
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Member Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest |
QUOTE(technicalninja @ Jul 13 2024, 11:26 AM)  On balancing... Pistons/rods I will balance to +/- 0.5 grams But the entire assembly I will accept +/- 2 grams. Doesn't have to be super close! When an engine runs it ends up with oil entrained on all of the parts and this oil "ropes" differently on different parts. Due to the amount of oil hanging on the parts the engine will NEVER be in "perfect balance". It CANNOT happen unless you get rid of the oil! Dry sump has less of this happening but it's still significant. When someone tells me the entire assembly is +/- some tiny amount it just means that they don't understand what is happening inside an engine while it's running... When a good machine shop calculates "bob weights" for a V engine they should ALWAYS include 5 grams for this entrained oil in each bob weight. Head porting photos. Just ordered AA 2 arm bench mount yoke. Looks pretty solid but will weld additional material if it looks questionable.   |
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Posts in this topic
Robroe 1.7 Rebuild First Start Up Advice Jul 4 2024, 05:15 PM
Montreal914 Cheap Amazon emdoscope connected to you phone shou... Jul 4 2024, 05:23 PM Superhawk996 With what you just described, I can’t see any sc... Jul 4 2024, 05:27 PM
bkrantz
With what you just described, I can’t see any s... Jul 4 2024, 08:29 PM emerygt350 When you say 'by hand', what do you mean? ... Jul 4 2024, 06:00 PM 930cabman
Have 73 1.7 bought in pieces. Engine has been reb... Jul 4 2024, 08:18 PM Superhawk996
. . . Or try the starter to spin it over. If you... Jul 4 2024, 09:38 PM Superhawk996
Without spark plugs the crank should rotate freel... Jul 4 2024, 09:55 PM Superhawk996
If you are unable to get a full rotation of the... Jul 4 2024, 09:52 PM emerygt350 You could remove the rockers and give it a go, if ... Jul 5 2024, 05:01 AM Robroe
You could remove the rockers and give it a go, if... Jul 6 2024, 12:02 AM emerygt350 I wouldn't worry about oil pressure yet but it... Jul 6 2024, 05:10 AM emerygt350 And it just occurred to me... Check top dead cent... Jul 6 2024, 06:15 AM technicalninja
With what you just described, I can’t see any s... Jul 6 2024, 07:15 AM Robroe
With what you just described, I can’t see any ... Jul 7 2024, 12:19 AM 930cabman
[quote name='technicalninja' post='3154991' date=... Jul 7 2024, 08:20 AM Robroe
[quote name='technicalninja' post='3154991' date... Jul 7 2024, 03:47 PM 930cabman
[quote name='930cabman' post='3155187' date='Jul ... Jul 7 2024, 03:54 PM Robroe
[quote name='930cabman' post='3155187' date='Jul... Jul 7 2024, 05:20 PM 930cabman
[quote name='930cabman' post='3155272' date='Jul ... Jul 7 2024, 05:46 PM emerygt350 Hopefully it was just crazy compression and stiff ... Jul 7 2024, 05:26 PM Robroe
Hopefully it was just crazy compression and stiff... Jul 8 2024, 02:40 PM 930cabman
Hopefully it was just crazy compression and stif... Jul 8 2024, 03:27 PM emerygt350 Wow, if that is right it is a monster. If you hav... Jul 8 2024, 02:59 PM Robroe Just remeasured stroke using plastic straw. 3.8â€... Jul 8 2024, 03:44 PM Robroe Boroscope just showed up. Pistons are marked 95.95... Jul 8 2024, 04:16 PM emerygt350 They look like my 96mm pistons. If that thing is ... Jul 8 2024, 04:19 PM Superhawk996 With respect to stroke - you’re neglecting that ... Jul 8 2024, 06:01 PM emerygt350 As long as the tip of the probe isn't sliding ... Jul 8 2024, 07:23 PM Robroe
As long as the tip of the probe isn't sliding... Jul 8 2024, 08:55 PM Superhawk996 Dude not even close to perpendicular to the dome o... Jul 8 2024, 08:47 PM Superhawk996
And this DVD available from LNengineering.com
Jul 8 2024, 09:56 PM Robroe
And this DVD available from LNengineering.com
... Jul 9 2024, 11:20 AM Superhawk996 You need to know the stroke, then you can determin... Jul 8 2024, 10:05 PM 930cabman There are literally dozens of things that should b... Jul 9 2024, 04:49 AM emerygt350 Or you could continue to determine if in fact you ... Jul 9 2024, 04:58 AM technicalninja I DON"T like the raised 95.95.
I want the to... Jul 9 2024, 07:09 AM Robroe
I DON"T like the raised 95.95.
I want the t... Jul 9 2024, 03:57 PM Robroe
[quote name='technicalninja' post='3155553' date=... Jul 9 2024, 04:00 PM Robroe
[quote name='Robroe' post='3155626' date='Jul 9 2... Jul 9 2024, 04:01 PM Robroe
[quote name='Robroe' post='3155628' date='Jul 9 2... Jul 9 2024, 04:03 PM technicalninja Tear down tip!
Keep everything in its origina... Jul 9 2024, 07:24 AM Jack Standz U can tell it's a stroker if you can see space... Jul 9 2024, 09:48 AM Robroe If I’m going to tear this engine down to inspect... Jul 9 2024, 11:35 AM 930cabman
If I’m going to tear this engine down to inspec... Jul 9 2024, 01:09 PM technicalninja THAT LOOKS PROMISING!
You might have hit a ho... Jul 9 2024, 04:29 PM Superhawk996 For OP
RAT = Raby Aircooled Technology
HAM = Ho... Jul 9 2024, 05:09 PM 930cabman
For OP
RAT = Raby Aircooled Technology
HAM = H... Jul 10 2024, 07:15 AM Robroe
For OP
RAT = Raby Aircooled Technology
HAM = ... Jul 10 2024, 06:00 PM technicalninja You couldn't have any better markings than tha... Jul 9 2024, 06:28 PM technicalninja Pull the tins FIRST!!!!
You want ... Jul 9 2024, 06:33 PM Superhawk996
Pull the tins FIRST!!!!
You want... Jul 9 2024, 07:00 PM technicalninja @SuperHawk996 :first:
Those are NICE!
Loo... Jul 9 2024, 07:53 PM Jack Standz That is some very good news for you. Those heads ... Jul 9 2024, 11:43 PM emerygt350 Man, I would hate to tear that down if it was prof... Jul 10 2024, 06:49 AM Superhawk996
Man, I would hate to tear that down if it was pro... Jul 10 2024, 06:55 AM emerygt350 First of all, looks like 2.0 heads to me. Cylinde... Jul 10 2024, 06:56 PM Robroe
First of all, looks like 2.0 heads to me. Cylind... Jul 10 2024, 07:15 PM Robroe
First of all, looks like 2.0 heads to me. Cylin... Jul 10 2024, 07:17 PM Superhawk996
What is a legion spacer?
looks like multiple sp... Jul 10 2024, 07:24 PM Superhawk996
I know all the old fuddy duddies are going to ti... Jul 10 2024, 07:19 PM technicalninja Positives:
Heads- look like Raby heads with weldin... Jul 10 2024, 07:26 PM burton73
Positives:
Heads- look like Raby heads with weldi... Jul 11 2024, 10:29 PM emerygt350 I think the raised numbers are just an optical ill... Jul 11 2024, 05:53 AM technicalninja 95.95mm in a 96mm bore equals .05mm PTW clearance ... Jul 11 2024, 07:26 AM Superhawk996
95.95mm in a 96mm bore equals .05mm PTW clearance... Jul 11 2024, 08:10 AM Robroe
95.95mm in a 96mm bore equals .05mm PTW clearance... Jul 11 2024, 11:33 AM Jack Standz
I guess I’ll wear the old fuddy duddie title w... Jul 11 2024, 08:48 AM technicalninja
[quote name='technicalninja' post='3155978' date=... Jul 11 2024, 11:25 AM technicalninja Piston to wall
Bore clearance. You measure the bo... Jul 11 2024, 11:48 AM 930cabman
Piston to wall
Bore clearance. You measure the b... Jul 11 2024, 12:14 PM Robroe
Piston to wall
Bore clearance. You measure the ... Jul 11 2024, 06:49 PM Robroe
[quote name='930cabman' post='3156016' date='Jul ... Jul 11 2024, 07:00 PM technicalninja Those have had the chambers worked far more than S... Jul 11 2024, 07:22 PM Superhawk996
Those have had the chambers worked far more than ... Jul 11 2024, 07:35 PM Superhawk996 So lighter than OEM con rods. Looking good.
Pi... Jul 11 2024, 07:27 PM technicalninja Did you check the stroke during disassembly?
You ... Jul 11 2024, 07:28 PM technicalninja The cast pistons, which I agree are FINE, need cle... Jul 11 2024, 07:32 PM technicalninja
Those have had the chambers worked far more than... Jul 11 2024, 07:46 PM Superhawk996
I'm actually in agreement with you. I did s... Jul 11 2024, 07:51 PM technicalninja SuperHawk, how would you test to see if the valves... Jul 11 2024, 07:55 PM Superhawk996
SuperHawk, how would you test to see if the valve... Jul 11 2024, 08:06 PM Superhawk996 I’m going to reiterate what Ninja said earlier
... Jul 11 2024, 07:59 PM Front yard mechanic We should change the name of this forum from 914 w... Jul 11 2024, 08:12 PM Superhawk996
We should change the name of this forum from 914 ... Jul 11 2024, 08:21 PM 930cabman
We should change the name of this forum from 914 ... Jul 12 2024, 06:25 PM technicalninja
I’m going to reiterate what Ninja said earlier ... Jul 11 2024, 08:15 PM technicalninja
We should change the name of this forum from 914 ... Jul 11 2024, 09:03 PM Jack Standz +1 on the suggestions to dynamically balance the m... Jul 11 2024, 11:59 PM Robroe Here are measurements so far. I still need cam li... Jul 12 2024, 04:51 PM technicalninja Good looking numbers!
I'd pick a single s... Jul 12 2024, 05:08 PM Robroe
Good looking numbers!
I'd pick a single ... Jul 12 2024, 06:25 PM Superhawk996
I need an engine stand yoke for my build. My wel... Jul 12 2024, 08:23 PM technicalninja I bought a cheap ass one as I was NOT planning on ... Jul 12 2024, 08:45 PM technicalninja https://aapistons.com/products/bench-mount-...AiAB... Jul 12 2024, 08:48 PM 930cabman
[quote name='technicalninja' post='3156410' date=... Jul 13 2024, 05:51 PM technicalninja Thanks for the pics!
Those ridges in the port... Jul 13 2024, 02:29 PM emerygt350 It looks like a ton of work for a little old 4, te... Jul 14 2024, 04:46 AM |
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