| Slant Six Forum https://www.slantsix.org/forum/ |
|
| Let's build a Sandman! https://www.slantsix.org/forum/viewtopic.php?t=63373 |
Page 3 of 5 |
| Author: | and739 [ Thu Apr 11, 2019 9:50 pm ] |
| Post subject: | Re: Let's build a Sandman! |
Good idea. I did and they all came in at 127g. Then I weighed them all together and took an average. 126.83g So my little scale is accurate to within one gram. I weighed the two heavy pistons, without the pins they lose one gram. Without pins my pistons are all within two grams of each other. I gotta stop before I go crazy. LOL Update: I stopped by the shop today. All the machine work on the block is done. He’s expecting cam bearings tomorrow. Then I’ll bring the block home Monday! |
|
| Author: | and739 [ Thu Apr 18, 2019 7:10 pm ] |
| Post subject: | Re: Let's build a Sandman! |
Monday I brought the block home from the machine shop. As suggested, I painted it right away. The machinist installed the cam bearings. He explained how he was careful to get them right. Tomorrow I'll drop off the new pistons to have then pressed onto the connecting rods. The moly rings are still backordered. |
|
| Author: | ProCycle [ Thu Apr 18, 2019 7:16 pm ] |
| Post subject: | Re: Let's build a Sandman! |
Quote: Monday I brought the block home from the machine shop. As suggested, I painted it right away. The machinist installed the cam bearings. He explained how he was careful to get them right. Tomorrow I'll drop off the new pistons to have then pressed onto the connecting rods. The moly rings are still backordered.
Did he have a cam to test fit? I've only built 2 Slant Sixes but both of them took quite a bit of 'clearancing' of the cam bearings to allow the cam to turn freely.
|
|
| Author: | and739 [ Fri Apr 19, 2019 8:04 am ] |
| Post subject: | Re: Let's build a Sandman! |
Good catch, ProCycle. Nope, the cam was at home packaged for shipment to OCG. After reading your post I came out to the garage, unpacked my cam and loaded it into the block (right after assuring spotlessness). I added a couple drops of motor oil to each bearing journal and spun the cam easily with the gear locating pin on the front. I didnt feel any catches and everything seems to be in alignment. Is there anything else I should look for at this time? Thanks for bringing this to my attention. I didn’t even consider this as being a potential problem. I’ll see my machinist later today and will ask about it. |
|
| Author: | ProCycle [ Fri Apr 19, 2019 12:51 pm ] |
| Post subject: | Re: Let's build a Sandman! |
You definitely had better luck that I did. If the cam spins freely you are all set. When it won't spin freely the standard fix is apparently to 'scrape the bearings until there is clearance. That sounds like butchery to me. I went another route. I made a 'reamer' out of an old stock cam by cutting notches at angles across the bearing bosses. I gave the cam reamer to Ceej after I was done with it. |
|
| Author: | and739 [ Fri Apr 26, 2019 9:28 am ] |
| Post subject: | Re: Let's build a Sandman! |
I picked up the piston/con rods yesterday. While at the shop I asked about the cam bearing install. He told me that he just used the standard cam bearing driver, nothing special. He did describe using the modified cam "reamer" on occasion for scraping the bearings when necessary. This weekend I plan to get the crank installed and check the oil clearances with Plastigage. I will also get pistons 1 and 6 in there to verify the new deck height. As long as one is careful, is it acceptable to install and remove the crankshaft? In his book, Doug recommends installing the camshaft before the crank but since I don't have a finished camshaft, it's obviously not ready to install. |
|
| Author: | DadTruck [ Fri Apr 26, 2019 10:29 am ] |
| Post subject: | Re: Let's build a Sandman! |
Yes, no problem with installing the crank to check sizing on the mains and to get deck height. You should not need to install the rings on 1&6 for the deck height, Be sure you get the crank set to TDC for the measurement. I like to use a dial indicator, the point where the dial changes direction is TDC. If you have you damper and front cover available, this is a good time to also verify that the timing mark on damper is correct. |
|
| Author: | DadTruck [ Fri Apr 26, 2019 10:32 am ] |
| Post subject: | Re: Let's build a Sandman! |
Yes, no problem with installing the crank to check sizing on the mains and to get deck height. You should not need to install the rings on 1&6 for the deck height, Be sure you get the crank set to TDC for the measurement. I like to use a dial indicator, the point where the dial changes direction is TDC. If you have your damper and front cover available, this is a good time to also verify that the timing mark on damper is correct. And it is not unusual for even flat top pistons to have a bit of a crown on them. Be sure to choose about the same spot on 1&6 for the measurements. |
|
| Author: | and739 [ Tue Apr 30, 2019 7:02 am ] |
| Post subject: | Re: Let's build a Sandman! |
I got busy this weekend and didn't get to work on the engine much, but I did get the crank in the block last night. The mains all checked good. They were right in the middle of the tolerance range. The crank spins free and generally feels good. Rods 1 & 6 were installed to check the new deck height. Oil clearance on them was just as good as the mains. Thanks for the heads up on the piston crown, DadTruck. Before installation I laid a straightedge across all the piston tops and it's easy to see the shape. I hope to get the measurements taken for the new deck height this evening. |
|
| Author: | Dart270 [ Tue Apr 30, 2019 8:38 am ] |
| Post subject: | Re: Let's build a Sandman! |
Wow, I admit I have never looked at crown on a "flat top" piston. Will do that. Sounds like good progress. Lou |
|
| Author: | and739 [ Wed May 01, 2019 11:42 am ] |
| Post subject: | Re: Let's build a Sandman! |
I made a troubling discovery last night. I measured the new deck height after having .060" cut from the block. I was looking to wind up in the neighborhood of .108" deck height. Number six piston: 0.099", Number one: .125". I re-measured different spots on each piston, same differential. I double-checked and made sure I hadn't slipped off of TDC. Still same. Then I thought the two pistons could be different. I measured the four remaining pistons, they were identical. I pulled one and six, they matched the other four. To eliminate any other variables, I installed one in the six hole, six in the one hole. Didn't change the measurements. I called the machinist. He was just as surprised as I am to hear the news. He said he machined it off the oil pan rail which should be parallel to the deck surface, correct? I've asked him to double-check my measurements when I bring it back to him on Friday. Has anybody else ever run into this? |
|
| Author: | Dart270 [ Wed May 01, 2019 2:17 pm ] |
| Post subject: | Re: Let's build a Sandman! |
I have heard of this, but never seen it on one of mine. Lou |
|
| Author: | emsvitil [ Wed May 01, 2019 4:14 pm ] |
| Post subject: | Re: Let's build a Sandman! |
So do pistons 2-5 incrementally vary between .099 and .125 ? |
|
| Author: | slantzilla [ Wed May 01, 2019 4:28 pm ] |
| Post subject: | Re: Let's build a Sandman! |
Mike had this issue once. It had something to do with the fixture the block mounted it. There was a bracket that held the block up slightly if you weren't careful putting it in. |
|
| Author: | Charrlie_S [ Wed May 01, 2019 5:02 pm ] |
| Post subject: | Re: Let's build a Sandman! |
I have never heard of setting a block on the pan rails for cutting the deck. The block should be set on the main bearing saddles, and the deck cut true to them. |
|
| Page 3 of 5 | All times are UTC-08:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|