Outbehindthebarn Posted September 24, 2016 Share Posted September 24, 2016 Does anyone on here know much about a small cam 400 magnum? Small cams were only sold up to 350h.p. in road equipment, correct? If I was re-powering an old truck that had a bad 335, would going big cam be a no-brainer? I kind of like the nostalgia of period correct power plants. Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/ Share on other sites More sharing options...
gearhead204 Posted September 24, 2016 Share Posted September 24, 2016 how much do you use the engine brake? as I understood it cummins main reason for the big cam was to better take the abuse of the engine brake( too many people figured out that a loose set slave cylinder would greatly increase the jakes strength) this puts more pressure on the exhaust lobes of the cam, thus causing cam falure. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346631 Share on other sites More sharing options...
Outbehindthebarn Posted September 24, 2016 Author Share Posted September 24, 2016 16 minutes ago, gearhead204 said: how much do you use the engine brake? as I understood it cummins main reason for the big cam was to better take the abuse of the engine brake( too many people figured out that a loose set slave cylinder would greatly increase the jakes strength) this puts more pressure on the exhaust lobes of the cam, thus causing cam falure. Yeah, I've heard they'd bend pushrods and generally hammered the top-ends, but the 400 magnum??? The one I'm looking at has chrome valve covers, after cooler.... factory according to the owner. Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346632 Share on other sites More sharing options...
theakerstwo Posted September 24, 2016 Share Posted September 24, 2016 The 400 magnum CPL 695 was a small cam and it was away of cummins to sell a rebuilt engine using the small cam block that they had so many of from trade ins on Big Cam engines.It had all of the components of a Big Cam 3.Low oil pressure and all.The lastest lub system and did a good job. 1 Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346634 Share on other sites More sharing options...
gearhead204 Posted September 24, 2016 Share Posted September 24, 2016 unless you are moving to Arizona I would rather have a 350, them damn 400's need an extension cord as soon as the temp drops below 42 degrees, just my two cents worth! Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346636 Share on other sites More sharing options...
theakerstwo Posted September 24, 2016 Share Posted September 24, 2016 (edited) The magnum is not that way.Its got same pistons as a BC 3 The NTA engines had a low compression piston and if it as 45 degrees or lower you had to use starting fluid. Edited September 24, 2016 by theakerstwo 1 Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346642 Share on other sites More sharing options...
Timmyb Posted September 25, 2016 Share Posted September 25, 2016 So your looking at a truck which originally had a 335 but has been repowered with a magnum 400? I wouldn't stress too much about it if that were the case. Sounds like it was something Cummins offered. Back when it was a working truck it would be a big plus! Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346659 Share on other sites More sharing options...
Outbehindthebarn Posted September 25, 2016 Author Share Posted September 25, 2016 Glen, what are they talking about when you hear people say off-set key? 1 Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346675 Share on other sites More sharing options...
Outbehindthebarn Posted September 25, 2016 Author Share Posted September 25, 2016 12 hours ago, Timmyb said: So your looking at a truck which originally had a 335 but has been repowered with a magnum 400? I wouldn't stress too much about it if that were the case. Sounds like it was something Cummins offered. Back when it was a working truck it would be a big plus! No the truck I'm looking at has a 335 that's bad, and I found this 400 magnum for a good price. Plus, it has jakes, which the 335 did not. Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346676 Share on other sites More sharing options...
Hobert62 Posted September 25, 2016 Share Posted September 25, 2016 If I remember right my dad said they use to put an offset key to retard the cam timing to make them pull better. Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346685 Share on other sites More sharing options...
Truck Shop Posted September 25, 2016 Share Posted September 25, 2016 1 hour ago, Outbehindthebarn said: Glen, what are they talking about when you hear people say off-set key? There was nothing wrong with the 400 Mag, had two in two Stars. Ran right down the road with the BC's. Plus that engine in the photo has a plus, the Bendix air compressor. The offset keys were nothing more than to advance or retard the cam timing. Truck Shop Quote One ping only Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346690 Share on other sites More sharing options...
Outbehindthebarn Posted September 25, 2016 Author Share Posted September 25, 2016 (edited) 3 minutes ago, Truck Shop said: There was nothing wrong with the 400 Mag, had two in two Stars. Ran right down the road with the BC's. Plus that engine in the photo has a plus, the Bendix air compressor. The offset keys were nothing more than to advance or retard the cam timing. Truck Shop What compressor is standard? And this does have the CPL 695. Edited September 25, 2016 by Outbehindthebarn Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346691 Share on other sites More sharing options...
gearhead204 Posted September 25, 2016 Share Posted September 25, 2016 alot of them had holset one lung compressors. so the truflo is almost a rare in that application for that vintage 1 Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346699 Share on other sites More sharing options...
theakerstwo Posted September 25, 2016 Share Posted September 25, 2016 That engine in the photo does not look like a magnum engine to me.A photo of the other side and numbers off the data plate who help but all magnum engine i was around had the steel oil pan with oil pump pickup tube at the front.And the oil pump will have a small oil line about six inches long connected to the oil pump to the oil galley of the engine behind the pump. Like been stated the off set key was for timing the cam to the gear.Small cams as well as Big cams could use it. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346703 Share on other sites More sharing options...
Truck Shop Posted September 25, 2016 Share Posted September 25, 2016 5 hours ago, Outbehindthebarn said: Glen, what are they talking about when you hear people say off-set key? There was nothing wrong with the 400 Mag, had two in two Stars. Ran right down the road with the BC's. Plus that engine in the photo has a plus, the Bendix air compressor. The offset keys were nothing more than to advance or retard the cam timing. Like said above it should have a steel pan for sure and BCIII oil pump. That Data plate on the accessory drive should say CPL 695 and the cam timing spec should say 56*. Plus the turbo should be the later Holset and it should have a pulse exhaust manifold on it. The injectors on those engines flowed allot of fuel and if I remember right the pump rail pressure ran higher than BC's Truck Shop Quote One ping only Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346710 Share on other sites More sharing options...
Outbehindthebarn Posted September 25, 2016 Author Share Posted September 25, 2016 1 hour ago, Truck Shop said: There was nothing wrong with the 400 Mag, had two in two Stars. Ran right down the road with the BC's. Plus that engine in the photo has a plus, the Bendix air compressor. The offset keys were nothing more than to advance or retard the cam timing. Like said above it should have a steel pan for sure and BCIII oil pump. That Data plate on the accessory drive should say CPL 695 and the cam timing spec should say 56*. Plus the turbo should be the later Holset and it should have a pulse exhaust manifold on it. The injectors on those engines flowed allot of fuel and if I remember right the pump rail pressure ran higher than BC's Truck Shop It does say 695. Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346712 Share on other sites More sharing options...
Outbehindthebarn Posted September 25, 2016 Author Share Posted September 25, 2016 2 hours ago, theakerstwo said: That engine in the photo does not look like a magnum engine to me.A photo of the other side and numbers off the data plate who help but all magnum engine i was around had the steel oil pan with oil pump pickup tube at the front.And the oil pump will have a small oil line about six inches long connected to the oil pump to the oil galley of the engine behind the pump. Like been stated the off set key was for timing the cam to the gear.Small cams as well as Big cams could use it. Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346713 Share on other sites More sharing options...
Truck Shop Posted September 25, 2016 Share Posted September 25, 2016 One thing I learned about Cummins years ago was that they put together many strange items to make engines. Just because it doesn't have or look to me that it has a stamped steel pan doesn't mean Cummins didn't build some with cast aluminum. If it has a data plate saying it is a 695 then it probably is. There really weren't that many sold so the plate is kind of rare it's self. Does the engine bar over 360*? Truck Shop Quote One ping only Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346718 Share on other sites More sharing options...
david wild Posted September 25, 2016 Share Posted September 25, 2016 I think someone has been eating to much CAT food, lota bad talk about perfectly good engines made by Cummins, and yes Cummins made plenty of cast pans. Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346721 Share on other sites More sharing options...
Truck Shop Posted September 26, 2016 Share Posted September 26, 2016 2 hours ago, david wild said: I think someone has been eating to much CAT food, lota bad talk about perfectly good engines made by Cummins, and yes Cummins made plenty of cast pans. Who has been eating to much Cat food? I haven't said one bad thing about Cummins, I ran four of them. Truck Shop Quote One ping only Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346744 Share on other sites More sharing options...
Timmyb Posted September 26, 2016 Share Posted September 26, 2016 So what era is the truck and 335 Cummins? Im guessing the big cam and magnum 400 was early/mid 80's? I bet there was lots of 335's changed out for either new engine through Cummins dealers. I wouldn't be too worried about doing that swap. But that's just me. I'd like to see the rig when the deal is done. Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346747 Share on other sites More sharing options...
gearhead204 Posted September 26, 2016 Share Posted September 26, 2016 must have been in the same era as the 475 twin turbo, strange I never saw this chromed up factory engine ever advertised, I always had my head buried in the trade rags from the late 70's thru the mid 80's Quote Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346753 Share on other sites More sharing options...
theakerstwo Posted September 26, 2016 Share Posted September 26, 2016 And the fuel pump has been changed because a magnum engine came with a AFC fuel pump.some one has stole the pulse manifold and Holset turbo.And also i have never seen them come from cummins with the chrome. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346754 Share on other sites More sharing options...
Outbehindthebarn Posted September 26, 2016 Author Share Posted September 26, 2016 (edited) 9 minutes ago, theakerstwo said: And the fuel pump has been changed because a magnum engine came with a AFC fuel pump.some one has stole the pulse manifold and Holset turbo.And also i have never seen them come from cummins with the chrome. Were there certain models that had factory chrome covers? And yes, he said that the manifold/turbo were robbed. Edited September 26, 2016 by Outbehindthebarn Quote Fun is what they fine you for!My name is Bob Buckman sir,. . . and I hate truckers. Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346755 Share on other sites More sharing options...
theakerstwo Posted September 26, 2016 Share Posted September 26, 2016 I would say someone has had those chromed which is common to do. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/46969-small-cam-cummins-questions/#findComment-346764 Share on other sites More sharing options...
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