MESABALANCING

As you would expect the blocks come from the manufacturers and they take even more work than the heads to get started.



Checking all the thread bores chamfering all the deck surface bolt holes magnetic particle inspection sonic testing and press testing once all that passes inspection they will go into machining. Here's a couple started today. These are 1 MB1100csefi or procharger efi set up and the 2nd is a MB900scefi or an entry level screw blower with EFI as well. I'll show every step along the way in the next couple of days. Hope you guys enjoy.

MESABALANCING

Finishing the lifter bores from a reamer finish to a finish hone with the clearance we run. We have had new blocks come through with the lifter bore being out of round as much as .008 and have actually found this in the inspection before we machine the block. We have also had engines specially engines that are purchased as short blocks through the mail order houses come through with stuck lifters is the block and damaged lifters from scoring due to the bores not being debured internally. This is not a very long process and eliminates many issues . When looking for reliability you can't leave any stone unturned.



We normally run .0020 clearance and also debur the internal oil gallery with a ball hone for eliminating the possibility of scoring the lifter body with any internal burs. At the end before it goes to assembly it all gets steel brushes for the final cleaning. Many complaints of lifter noises can be eliminated by inspecting and knowing what the lifter clearance actually is before assembly. Hope you guys enjoy. Sincerely Laz

mike tkach

iTrader: (3)

laz,just about every dart block i have seen needed the lifter bores resized,they tell you in the paperwork that comes with the block that the builder needs to do so.i recently did two 525 engines that needed new blocks,i bought the gm over the counter blocks that come fully machined,everything was machined spot on but they did a chit job of deburring them.they had a really nice hone job and the rings seated quickly.under 2 grand for a fully machined gm block seemed like a fair deal to me.

MESABALANCING

Mike you know GM stuff is hard to beat sometimes and they'll hold some power too. I'll be honest what I like the best about the Dart and Merlin stuff is being able to machine it where we want it for clearance and finish . One thing I have never been a fan of the GM stuff is the deck surface finish but you know that's easy to fix too. Thanks for your reply that's also very good for the guys from OSO because sometimes when the budget is not there they have that option as well. The most important reason for these post is to inform the guys here so as to understand were some of these problems they have come from and to not let shops take them in the wrong direction . Sincerely Laz

MESABALANCING

Here's a picture of the cylinders being finished in a Dart block with a custom gasket from torque plate. Again finishing for clearance and surface finish for the rings we are using.



This is the first of 4 finishing stones we use for the proper finish



Here's the finished product not cleaned yet and also the deck surface machined .

MESABALANCING

Got the blocks preassembled and working on setting the final piston to head clearance and static compression by decking . Also something else to be said these blocks come through un finished new out of the box they have steps on the deck surface from the manufacturing process. This is an area which I have seen many mail order short blocks come through un finished which will cause head gasket sealing problems as well as temp issues and water and condensation in the oil all problems that arise on the forums all the time and guys pull their hair out trying to determine were it's coming from. Also GM blocks that come finished and ready to run if you ever pull a GEN V or VI apart you will see in the lower cylinderhead bolt holes between the two center bolts they all leak in the area they all need to be properly machine with the correct finish to avoid this.





In the picture above you can see after a light skim cut two areas on either side of the water passage were the factory machining was not flat this particular case the coolant would leak out from the deck but there are also areas were you would not be as fortunate and can lead to condensation in the oil.

MESABALANCING

Hey guys today's bottom end update. I hope you're all well here are some pics of the bottom ends going together after checking bearing clearances .



Here block needs rear seal installed to drop the crank in. Check out the bottom of the cylinders chamfered and also very important when you purchase a new Dart of Merlin block chamfer the freeze plug bores they come with a sharp edge and will scar the seal when installing it which will cause leaks or worse the plugs to blow out under high water press. These are two things which look insignificant but are very important. If you've ever had an engine built and saw scratches at the bottom of the bores most likely the edge at the bottom of the bore was never chamfered.



After crankshaft install the very first thing check the thrust clearance or endplay . I personally set this by leaving the rear main cap torqued to 5 ft lbs. and tap the crankshaft with a heavy hammer by the snout using a machined bar to keep from damaging the front of the crank and then tighten the cap to the proper torque and checking. Make sure the indicator is always straight with the centerline of the crankshaft. If you don't have an indicator it's a bit more work but you can slip a feeler gauge between the crank and the bearing.

Thunderous

Awesome threads from you guys, thanks for sharing. Your attention to clearance detail is what separates "engine assemblers" from real blueprint and balancing shops. Surprising about the Dart blocks though. I run their 302 Iron Eagle blocks in my vintage race cars and they are the highest quality, most precisely cast blocks we have ever seen. Wonder why the difference, especially with the pushrod clearance...

MESABALANCING

Today's progress got short blocks together and ready for oil pans next.


Here one short block finished and the second in the works.



Back out of the engine assembly room for a quick quality control inspection of all thread bolt bores and installation of pan and head studs then back into the engine assembly room for cylinder heads and valve trane assembly. Camshaft already installed and degreed.

AZMIDLYF

Great thread..Thanks for taking the time.