mainer311 Posted October 16, 2019 Report Share Posted October 16, 2019 I'd just run it. Do a quick hone to scuff up the walls for new rings and put it back together. Quote Link to comment
datzenmike Posted October 16, 2019 Report Share Posted October 16, 2019 3 hours ago, d.p said: @datzenmike Did you read what I originally posted? The cylinders mic'd at 3.389 and the pistons anywhere from 3.385 - 3.389 IIRC. He also said that he thought it would all work fine. I got no interest in going 1.5mm over either so if I can make what I have work I will. Yup 3 hours ago, d.p said: Machine shop called with an update on my l20b and said he thinks the block would be fine with just a clean and bore. Hasn't got to the head yet but did share his measurements on the bottom end. Cylinders at 3.389 Pistons 3.385 - 3.386 He said standard 1mm over would be 3.386 and that it looks to him like it was bored .0003 over on purpose. Is that typical? So 0.004" to 0.003" above the factory recommended 0.0018" piston to wall side clearance. Give it a try.... 1 Quote Link to comment
d.p Posted October 16, 2019 Author Report Share Posted October 16, 2019 @Stoffregen Motorsports @banzai @Crashtd420 anyone else got any input on this? I certainly don't want to put it back together and have it issues with it because the clearance was to high. 1 Quote Link to comment
mainer311 Posted October 16, 2019 Report Share Posted October 16, 2019 (edited) 1 hour ago, datzenmike said: Yup So 0.004" to 0.003" above the factory recommended 0.0018" piston to wall side clearance. Give it a try.... Do you suck at math or what? His current measurement are 3.389 for the cylinders and the pistons range from 3.385 to 3.386. That gives a radial clearance between .0015 and .002. Edited October 16, 2019 by mainer311 1 Quote Link to comment
banzai510(hainz) Posted October 16, 2019 Report Share Posted October 16, 2019 DP your over thinking things. He said your fine. Is Macinist thinking of using the same old pistons or new of the same size as it is. Why I say this is the piston side wall might be thinner and some machine shops don't like this as its not totally perfect. Esp if one tries to warrenty the motor. If this were me I would hone it and just rering it and call it good. i don't want to pay for the machining out of the bores. pistons are cheap in most stock cases but its hard finding the next up size sometimes as these parts are not avail. 1 Quote Link to comment
d.p Posted October 16, 2019 Author Report Share Posted October 16, 2019 (edited) 29 minutes ago, mainer311 said: Do you suck at math or what? His current measurement are 3.389 for the cylinders and the pistons range from 3.385 to 3.386. That gives a radial clearance between .0015 and .002. Radical...lol should have left it like that my dude. Is that how it works? Radial, so if it is .003 then its .0015 gap between the piston and cylinder all the way around? I posted on FB in the church of L series group as well and those dudes seem to agree with Mike that if there is .003 of clearance between the cylinder and pistons than the pistons are junk. Said only fix is to bore it out and go up a size which I really didn't want to do. 7 minutes ago, banzai510(hainz) said: DP your over thinking things. He said your fine. Is Macinist thinking of using the same old pistons or new of the same size as it is. Why I say this is the piston side wall might be thinner and some machine shops don't like this as its not totally perfect. Esp if one tries to warrenty the motor. If this were me I would hone it and just rering it and call it good. i don't want to pay for the machining out of the bores. pistons are cheap in most stock cases but its hard finding the next up size sometimes as these parts are not avail. Would it be me if I didn't? He said he could use the same ones. He said he could order me rings to once he gets to that point. lol I do tend to ask advice from too many people which gets me in trouble sometimes. Like I just completely redid my entire lawn and asked the local guy how much seed I should use and he told me 100lbs for 5000 sqft which is about 75lbs too much. Luckily I didn't use that much..used 50lbs but still ended up overcrowding and killing off a ton of new grass. Edited October 16, 2019 by d.p 2 Quote Link to comment
mainer311 Posted October 16, 2019 Report Share Posted October 16, 2019 (edited) Yes. The measurements he gave you are diameter, so you subtract the piston from the bore, and divide by 2. In a perfect world, the piston is completely round and centers itself, so the clearance would be uniform all the way around. Edited October 16, 2019 by mainer311 1 Quote Link to comment
datzenmike Posted October 16, 2019 Report Share Posted October 16, 2019 Wasn't sure if all the way round. 1 Quote Link to comment
mrbigtanker Posted October 16, 2019 Report Share Posted October 16, 2019 3 hours ago, d.p said: Dude that’s your house man I love it. 1 Quote Link to comment
mainer311 Posted October 16, 2019 Report Share Posted October 16, 2019 Wish my lawn looked half as good as that. Some kind of weed killed half my shit this summer. 2 Quote Link to comment
d.p Posted October 16, 2019 Author Report Share Posted October 16, 2019 Yeah that’s my house. Mainer you got to kill it all with glysphate in August and then seed Labor Day weekend, water the shit out of it and hope nothing kills it off. Unfortunately for me I used way too much seed and it choked out a lot of the new grass. I am sure it will be great come spring but nothing tries your patience more than a lawn. Labor of love if there ever was such a thing. Back to my engine. So I should be good to use my pistons with a slight hone and new rings? 1 Quote Link to comment
Charlie69 Posted October 17, 2019 Report Share Posted October 17, 2019 (edited) Make sure your ring end gap is good and your rings are spaced correctly on your pistons. If they are to tight you will feel it turning the short block assembly with a ratchet and a socket. If the are to loose chances are you will here piston slap when you start it. Edited October 17, 2019 by Charlie69 Quote Link to comment
d.p Posted October 17, 2019 Author Report Share Posted October 17, 2019 8 hours ago, Charlie69 said: Make sure your ring end gap is good and your rings are spaced correctly on your pistons. If they are to tight you will feel it turning the short block assembly with a ratchet and a socket. If the are to loose chances are you will here piston slap when you start it. machine shop going to gap/install them for me once we determine which ones to buy. 1 Quote Link to comment
Stoffregen Motorsports Posted October 17, 2019 Report Share Posted October 17, 2019 22 hours ago, d.p said: @Stoffregen Motorsports @banzai @Crashtd420 anyone else got any input on this? I certainly don't want to put it back together and have it issues with it because the clearance was to high. Have them measure an old piston and the bore. If the piston to wall clearance is more than a couple thousandths out of spec, have it bored. If it's only a little loose, just run it. Gap the rings accordingly and you won't ever notice a thing. If the bore is out of round, then this might change things. You may be forced to have it bored. Quote Link to comment
d.p Posted October 17, 2019 Author Report Share Posted October 17, 2019 26 minutes ago, Stoffregen Motorsports said: Have them measure an old piston and the bore. If the piston to wall clearance is more than a couple thousandths out of spec, have it bored. If it's only a little loose, just run it. Gap the rings accordingly and you won't ever notice a thing. If the bore is out of round, then this might change things. You may be forced to have it bored. They did, cylinder bore is 3.389 and the pistons measured between 3.385 - 3.386. I guess my plan now is just to gap the rings accordingly and 'send it.' 2 Quote Link to comment
d.p Posted October 26, 2019 Author Report Share Posted October 26, 2019 Battery problems with my H4 headlights on. Drove the truck today maybe 10 miles (20 minutes or so) with the headlights on, stopped, turned it off let it sit for maybe 5 minutes then it wouldn't start at all. Turn the key and and nothing, not cranking or turning over. Got it jumped and it started right up, drove home with the lights on and about a mile from my house it died again and had to jump it again to get it going. My cig amp meter says anywhere from 13.5-15 amps when driving, hovers around 13.x with the headlights on but it seems like they are either robbing all the juice or I got some other problem going on. Charge light doesn't come on at all so I maybe my H4 harness isn't working right? Quote Link to comment
datzenmike Posted October 26, 2019 Report Share Posted October 26, 2019 I swapped halogen lamps into my 521 back in the 70s. Made the mistake of driving slowly with high beams on and emptied the battery making restart only possible with a push. They draw much more power than the originals and the alternator isn't that powerful at 34 amps. An amp meter is only good when you know what amps you are supplying. If 13.5-15 amp draw, but only making 10 of those amps driving the battery won't charge. A volt meter is better. Does the red light come on with the key on but not running? Quote Link to comment
d.p Posted October 26, 2019 Author Report Share Posted October 26, 2019 Yeah the red light comes on when I turn the key so I know its working. But i thought the harness relay I got would run the H4s off the battery so it would be non-issue but I have been wrong before. Quote Link to comment
datzenmike Posted October 26, 2019 Report Share Posted October 26, 2019 With an upgraded harness they will draw their maximum current, which is fine because maximum light is the intent. Was this only on low beams? 13.5 to 15 amps is almost half the rated output of the 521's alternator. Was there anything else 'on' at the time? certainly the ignition and all the rest of the lighting (side marker, parking, running and license plate as well as the dash lights) It adds up. How is a cigar lighter going to measure amps? you sure it isn't volts? Quote Link to comment
mainer311 Posted October 26, 2019 Report Share Posted October 26, 2019 44 minutes ago, datzenmike said: How is a cigar lighter going to measure amps? you sure it isn't volts? I was just going to say the same thing. You can’t measure amps via the cig lighter. Ammeters work by being a fusible link, and the entire system needs to run through it to work properly. Voltmeter reading 13.5-15 sounds perfectly fine. Usually a properly charging alternator will read around 14.2-14.5 depending on the state of the system. Quote Link to comment
d.p Posted October 26, 2019 Author Report Share Posted October 26, 2019 Yeah that’s what Ii meant volts. Nothing else on just the cluster and the head lights (Low beams). I got nothing else to turn on anyway except for the heater. Radio isn’t even hooked up. And that’s what it’s been reading BUT when it died or wouldn’t start it was reading like 9 VOLTS or less. I just went to start it right now and it’s completely dead so I threw it on the charger. Quote Link to comment
Crashtd420 Posted October 26, 2019 Report Share Posted October 26, 2019 How old is the battery? Sounds like you might not actually be charging the battery as you drive.... Possibly only running off the alternator.... After you get the truck running test the voltage at the battery posts to make sure its charging the battery.... What is voltage of the battery just at rest.... Even a good but dead battery at rest should show 12.5 volts.... Anything less means you have a cell or 2 dieing in the battery.... Quote Link to comment
Crashtd420 Posted October 26, 2019 Report Share Posted October 26, 2019 So was it 9 volts when you turn the truck on or while trying to crank the engine ... There will be a voltage drop during the crank cycle.... Quote Link to comment
d.p Posted October 26, 2019 Author Report Share Posted October 26, 2019 Battery is at least 3 years old. Not sure how long the PO had it installed. truck off meter reading 11.2 turn key on reading 9.1 try to start everything just turns off I am going to grab my voltmeter and test from the battery. Quote Link to comment
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