Hemi crate motor problems continued

Discussion of Hemi crate engines.

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Hemi crate motor problems continued

Post by biggymu » Sun Jul 04, 2004 10:23 am

Hello to all, I am new to your forum and I am interested in sharing my misfortune in purchasing my 426 hemi crate motor. I purchased mine in 2002 and trans planted it in a 70 dart swinger with 4 speed trans. The new motor started popping over 3000 rpm and after some trouble shooting,it was discovered that all the exhaust push rods were almost a quarter inch too long. It took 2 months to get Chrystler to admit to their wrongdoing. In the mean time I got in touch with John Aruzza who provided me with the correct length rods. The rocker arm shaft oil plug blew out a week after I got it running again. I fixed that and again ran the car for a month before hearing loud valve train noises. I discovered 4 lifters had failed catistrophically ,breaking apart and sending metal fragments throughout the motor. After carefully cleaning and replacing all offending components the motor ran strong for about 6 months before swallowing an exhaust valve, destroying head ,cylinder wall, and piston. I let the car sit for about 18 months being financially unable to effect repairs. Ths past month I shipped the whole pile of crap to John Aruzza(A true Gentleman througout the series of disasters) He was always quick to offer advise and vast knowledge to me even though he had nothing to do with the motor's origional building. He told me these motors had about a 70 percent failure rate and were in many cases viewed as nothing short of sabotaged. There are no bronze valve guides in the heads, geometery was all messed up, rings never sealed, He has seen these engines missing rings on one piston, missing bearing shell halfs, fingertight headbolts,etc. I could go on and on. I love this car and motor and have waited my entire life to put together such a combination. But I would advise anybody thinking about buying a Chrysler Hemi crate motor to reconsider it. I think after spending now about 22,000 dollars that I had a respected motor builder make me one from scratch in the first place.Is there a class action lawsuit anyone knows of out there that I can get involved in? Mr. Aruzza said he would testify as a expert witness. Sorry I am a diehard Mopar fan but I cannot sugar coat my dissappointment in choosing thier crate motor. :cry:

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Horror stories

Post by cuda70 » Fri Jan 28, 2005 3:10 pm

Problems with crate’s is certainly not limited to Chryslers. My friends in the Chevy world are reporting the same thing with Chevy crates. The word is that "crate motors" (although are to spec) are not built with premium parts. I'm willing to bet any crate hemi does not come with a billet crank or even pistons from a reparable company like TRW.

EVERY engine builder I have talked with recommends buying a bare block and build it yourself with race quality components. The cost is about the same but the engines strength is like night and day. There are many good designs that can be followed so all you really are doing is assembling.

I have been exploring crate engines for my Cuda. I have also heard the horror stories.


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Crate engine problems revisited

Post by biggymu » Fri Jan 28, 2005 6:01 pm

Some time has elapsed since my original post and I just this last week recieved my new Aruzza built 472 duel quad motor that was sent to him in a basket 8 months ago. John has let me in on some other problems going on in the parts world, buyer beware! I had purchased a complete cylinder head to replace the one destroyed in paragraph one above. The brand new 1300.00 head had so much core shift in the casting as to make it almost unuseable. 20 hours on the grinder to make work! Also there are many of these heads in circulation. Mopar was selling these as top quality new production parts. As well with the forged rocker arms. The geometry is so incorrect that they peened the tops of the exhaust valves into mushrooms after about 100 hours of running time. Its gonna take a few weeks to squeeze this big thing back into my dart but I can guarentee Its going to be no comparison to the crap I had bought in good faith with my hard earned money From Mopar Performance. Please do youself a favor Have a builder make you one. Almost any lawnmower shop can equall the quality of my first mill. John Aruzza is tops! :evil:

mr fabrication
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Post by mr fabrication » Wed Aug 09, 2006 9:30 pm

was just wondering how your hemi worked out .I was thinking of buying one but after hearing about all of everyones problems i may just build one.

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Post by Jess69Charger » Sat Oct 07, 2006 12:47 am

Joined the site today, and this is not what I was hoping to hear at all. I came here trying to decide which Crate to go with. Maybe a Crate's not the way to go at all.

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Post by Bailiesdad » Sat Oct 07, 2006 8:29 am

Crate hemi is a good way to get all the parts in one purchase, then perpare them for use.

R/T Jack
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Post by R/T Jack » Sat Oct 07, 2006 3:29 pm

I would go with a specific builder such as: www.forhemisonly.com or www.bestmachineracing.com

I haven't heard of anyone who is happy with their crate motor from Mopar.
Last edited by R/T Jack on Sat Oct 21, 2006 10:48 pm, edited 1 time in total.

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Post by hemidup » Sat Oct 21, 2006 12:55 pm

Denny put a MP 472 crate in a 71 Challenger. The fuel pump was defective from the start and the rings still haven't seated after 1000 miles. It's getting better though. Better than 1 qt of oil to the first 70 miles of driving.
392 Blown Hemi

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Post by hobbeekid » Mon Dec 04, 2006 7:59 pm

Ya know, in spite of all the horror stories if I had the extra dollars I'd probably splurge & buy a crate hemi but Id be sure to pull it apart and inspect everything before reassembling & firing it. I presantly have what will be a 472 that I've been gathering parts on for the past 10 years. I've never had the $$$$$ to go buy a new crate motor so this is how I'm getting it done Hell I don't even have a car to put it in yet.May never find one with the prices mopars are at these days. :cry: Guess It'll become a rec room coffeetable instead........

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Re: Hemi crate motor problems continued

Post by oldngood » Mon Oct 05, 2009 7:47 am

old thread, kind of disturbing, but a word to the wise- in today's political climate, with Chrysler being bailed out and bought by Fiat (did that actually really happen now ??)- I doubt the crate Hemi will be around much longer at all. Get 'em while you can, they will go the way of the do-do bird soon. A Hemi is viewed as being environmentally damaging and a "dirty" engine by these green d-ck hippies and yuppies. They want us all driving around in electric cars.

The reason some of these engines have such bad quality problems, is the workforce that assembles them- I saw the UAW workers on TV earlier this year, and I would not want them assembling a toaster for me, let alone my car or engine. The quality and intelligence of the workforce has suffered dramatically at the Big Three- there's just no enthusiasm for making cars, no excitement. They toured the factory and it was like a morgue.

one Buick worker didn't even know the difference between a traditional Buick or Olds advertising commercial, i.e. "this is not your father's Oldsmobile"- he had no clue what the interviewer was talking about. That would be like a scientist who never heard of Einstein. The new generation of UAW workers are not motorheads, they just put their time in and assemble cars- they could care less about quality. It's all about what's in it for them financially- and this "green" buzzword reminds me of the pet rock and smiley face fads of the 1970's.

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Re: Hemi crate motor problems continued

Post by biggymu » Thu Nov 03, 2011 6:45 pm

Sorry Gentlemen. As you can tell by the number of years that have elapsed since my initial rant that I have been very happy with my Aruzza built 472 Hemi Dart. This car will smoke the tires at 60 MPH. It has the potential to kill the unwary. I have no idea what the top end is .I chickened out at 140 in 3rd gear. In the almost 10 years I have had this engine it has never once failed to start or failed to thrill. It starts and runs like a grocery getter. Mr Aruzza gives personalized service over the phone that you will not find anywhere else. He is the fanatically fussy person you want where your money is concerned; especially when you might have to squeeze an elepant sized motor in a itsy bitsy engine bay. I do not want to have to go through that again.We are talking about a person who has built motors for Richard Petty,Petty's father, and even the guy who designed the hemi itself back in the 1960's! Check out his web site Aruzza Performance. If youir lucky enough to have this man build for you I guarentee your satisfaction. I will try to post a few pictures. Im not much of a computer guy so here goes Good luck to all. Best Rick
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Re: Hemi crate motor problems continued

Post by biggymu » Thu Nov 03, 2011 6:52 pm

Here is a couple more
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Post by mart » Thu Nov 03, 2011 10:57 pm

hemidup wrote:Denny put a MP 472 crate in a 71 Challenger. The fuel pump was defective from the start and the rings still haven't seated after 1000 miles. It's getting better though. Better than 1 qt of oil to the first 70 miles of driving.
I'm not saying anything good, bad or indifferent about the 426 Hemi "crate engines", as I don't have any experience with them. But I do recall some first hand experiences with a few factory Hemi cars from 'back in the day' when you could buy or order one brand new, off a dealers lot - including, in particular, a buddy's nearly new '71 Hemi Roadrunner, that he had, circa 1972-'74. I certainly hope your rings do seat soon and that your oil consumption radically improves - but even fully broken-in and running well, don't expect anything like normal or average "new car" oil consumption. 'Back in the day', it was not uncommon for stock, factory assembly-line-built 426 Hemi cars to average about 800 to 1000 miles (and sometimes a bit less even!) - to a quart of oil. It was just the nature of the beast and the fact that as a basically and only slightly de-tuned 'race engine' - most Hemis usually came off the assembly-line, built closer to the loose side of the factory tolerances, to minimize internal friction. It also wasn't uncommon for anyone looking for maximum performance from their new "Street Hemi" ride to tear the engine apart and at least blueprint it (and usually go to the aftermarket for some upgraded parts, too) within the first 10,000 miles or so. Because of this, most dealers even would try to steer any customers who weren't really hardcore gearheads prepared to do a lot of extra work and not complain about things like oil high consumption, into buying a milder but much more "daily-driver-friendly"- and in stock form, at least, nearly as quick - 440-powered car.


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Re: Hemi crate motor problems continued

Post by biggymu » Fri Nov 04, 2011 7:22 am

The fuel pump rod is a big problem, its not hardened properly and will send metal through out the engine. John Aruzza would not even warranty the motor unless I agreed to get an electric pump and regulator. This motor does not burn oil. If you read machining operations on Aruzza performance web site, his blocks spend about 4 days getting the cylynder walls honed. No one else does this. The rings seat nicely. Going back to the crate motors being built "loosely"..... mine was destroyed by the fact MP used 10 degree locks and 12 degree valve retainers. It swallowed a valve at 5000 rpm. Yea the parts fit loosly. So loose the thing ate itself up. I love mopar but screw MP. I couldnt get past the monkey on the tech line until I threatened them with legal action. Always get your motor built but a pro.

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Re: Hemi crate motor problems continued

Post by speedicusmaximus » Sat Nov 05, 2011 12:56 pm

Is that Hemi really as tight as it looks ? I know they weren't a loose fit in the A-bodies, but that doesn't look as if there's room for the engine to move under throttle response !

Neat though !

Beep ! Beep !

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Re: Hemi crate motor problems continued

Post by biggymu » Sat Nov 05, 2011 2:47 pm

Yes it really is that tight. I wanted to keep my hood clearance at all costs, as I love my scoops! So I had to lower the K member down 5/8". This had the effect of making the wedge wider and lower. I had to relieve the passinger side shock tower just a little, moved the blower motor into the firewall, move the master cylinder.etc. I made the base of the air cleaner assbly out of a new 6 pack repop.... shifting the assbly to the drivers side and bending the air cleaner studs with a torch. I cannot even use a vented radiator cap or the hood wont close. The motor mounts were rubber oem units but they soon started to cause trouble. Over time the rubber settled and allowed the drivers side cylinder head to make contact with the steering shaft (disconcerting!). I replaced the rubber element in the mounts with an 1 1/4 " block of steel painted black. It now has solid motor mounts and does not move short of twisting the frame. The headers were almost 8 hours a side to install. This was part of the project that has to be done completely out of love. You could not pay someone enough money to connect the headers on this car. I am a seasoned mechanic; I fear little that is mechanical,or electrical but this was a brutal, miserable task. Each header pipe is 2 1/4" in diameter and each pipe is separate from the others. They had to be woven through the torsion bars,steering gears and arms,etc. in several cases the factory bends were not correct and the pipe had to be bashed, hammered or bent into the correct relation,thus knocking off the fresh Jet Hot coating (I do not have personall access to exhaust modification tools). At any rate once all was in place and the car was running I had the car put on a lift and corrections made to any offending pieces of tubing. I think if the starter ever goes bad (it had to be customized it a cut off wheel to allow the clutch to operate freely) I will consider being buried in the car before I remove the exhaust systen again. But thats why we do what we do anyway. If it wuz easy.... :o

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