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Moses Ludel

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About Moses Ludel

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    Reno Area...Nevada
  • Interests
    Family, destination four-wheeling and dual-sport motorcycling, photography, videography, fly-fishing, anthropology, automotive mechanics and welding/metallurgy.

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  1. Umm...Well, Tawanda, the Clifford manifold was traditionally a 4-barrel flange pattern. Many adapted 2-barrel Holley carburetors to the Clifford intake manifold, using a common 2-barrel to 4-barrel adapter plate. You need an adapter plate to mate Howell's TBI (GM TBI base pattern) to either a Clifford or Jeep 258/4.2L stock manifold. Howell's kit does furnish an adapter to the Jeep manifold. There are many adapter plates for a GM TBI unit to a four-barrel carburetor pattern like the Clifford manifold. I found this inexpensive example at Amazon: Transdapt 4-barrel manifold to GM TBI Unit. You would need to confirm that this plate would work with both the Howell TBI unit and the Clifford manifold. From my vantage, the gains of TBI far outweigh the concern about less than ideal air flow to the end cylinders. If Howell does not support the switch to a Clifford manifold, I would stay with a stock BBD manifold and, by all means, get the emission legal Howell TBI conversion. It will not produce the horsepower of MPI (Mopar's kit) but will provide a reliable and substantial improvement over a carburetor. Carburetors with a float and fixed jets or fuel circuits are sensitive to off-camber (tilted) trails and altitude changes. In the early nineties, I tested a Holley 2300 two-barrel carburetor on a 258 Jeep six. Horiba lent me $10,000 (very expensive at the time!) worth of air/fuel ratio testing equipment. The popular Holley Universal 300 CFM carburetor, jetted and metered for sea level, showed significant enrichment with each 1,200 feet of elevation change. Each fuel ratio change would require re-jetting to restore a normal air/fuel ratio (14.7:1 "stoichiometric" at cruise). Engineer Pass in Colorado is 12,800 feet above sea level. An EFI system (TBI or MPI) with oxygen sensor feedback can compensate for this. A non-feedback carburetor cannot. Even the eighties feedback carburetors could not adjust for this range of atmospheric change. That, in part, ushered in the era of TBI and port or multi-point injection. I respect the Clifford products, and the tuning of the dual Weber carburetors is likely well tested. The system looks clean, complete, well conceived and performance oriented. Predating modern EFI systems, Weber carburetors earned racing and high performance laurels in European marque cars. I'm sure the Clifford header complements this induction system, the combination packing a performance wallop. Add a re-curved aftermarket ignition distributor, a compression bump and performance camshaft, and this would be the ultimate inline six-cylinder AMC/Jeep performer for sand drags or hill climb competition. However, like other aftermarket carburetors, Weber carburetors are altitude sensitive and do not have an oxygen sensor feedback system. (The later Jeep/Carter BBD carburetor has an O2 sensor although its function is very limited and aimed mostly at meeting emission requirements—not improving performance.) An aftermarket four-barrel or dual carburetor conversion is not 50-State legal and comes with an "off-highway use only" disclaimer. For driving in rough backcountry, Howell's TBI kit offers better rock crawling stability than carburetion, plus the kit is 50-State legal. It sells for half the current price of a Mopar EFI Conversion Kit. The Sniper and MSD Atomic systems perform well, but what about proprietary replacement parts? Specifically, a Jeep 4x4 needs backcountry reliability, ease of service and ready parts availability at the local auto supply on a Sunday afternoon. Many of us have made parts runs to Auburn, California on behalf of Jeep 4x4s stuck along the Rubicon Trail. Beyond carrying a spare electric fuel pump, you can find common GM TBI parts at most local parts houses. At least the parts would be recognizable. To the point, Sniper and Atomic systems are fantastic for street rods, hobby cars, restomods and drag strip performance. You have a Jeep 4x4. Decide what will best meet your needs. Choose the fuel and spark system that will reliably get you home from the woods. Moses
  2. tshasha...Although your scanner may be accurate, I would run some manual tests. With an infrared non-contact thermometer, see what the actual temp is at the thermostat housing and radiator. If it's truly 155 degrees F after warm up, change the thermostat to a new 195-degree F unit. See if that takes the system out of open loop and stabilizes the idle. As for manifold vacuum, same thing. Check the actual manifold vacuum with a simple vacuum gauge at a manifold port below the throttle body. These mechanical tests will indicate more than a scan, as the scan tool depends solely on sensor and ECU data. If the problem persists after these checks and repairs, test the pressure at the TBI pressure port. It should be 14-15 PSI. Verify that the fuel pump part number is correct for a 2.5L TBI application. A later pump application for MPI will put out too much pressure. Let's go from there... Moses
  3. Well, pwbulldog, that does account for a part that resembles #1 in the 1981 Mopar Parts illustration below. Though not your 1977 model, the bracket for a column shift steering column is similar. Sounds like you nailed it. The other piece fits there too?
  4. I have no illustrations from the pre-1981 parts manuals. Your components do not resemble frame members or engine/transmission support brackets. A late seventies (1976-79) factory parts schematic for the body and attachments would be helpful. This is the 1981 Mopar catalog/factory body tub and dash layout. Though not your model, this may be insightful: Moses
  5. Simon...Like you discovered, everyone has the 304/401 V-8 dipstick tube and oil level stick for your era Jeep. I searched and found nothing for the 4.2L inline six. My OEM part numbers go back to 1981. For 1981-82 Jeep models, I found the 4.2L dipstick and tube. (The change year appears as 1983.) Here are those Mopar part numbers: TUBE, Engine Oil Indicator J3176846 1981-82 INDICATOR, Engine Oil Level J3237515 1981-82 I dug further, and Crown Automotive offers the tube, which is available at Quadratec. This tube is backward compatible to your model: https://www.quadratec.com/p/crown-automotive/engine-oil-dipstick-tube-jeep-cj-sj-and-j-series-6-cylinder-engine Try contacting Crown or Quadratec about a matching dipstick for this tube...The oil level stick should be the same part as the Mopar J3237515. Moses
  6. pwbulldog...I hunted the internet until these late seventies CJ 4.2L water pump photos turned up. (Photos courtesy of http://jeep.smallcraft.net/.) There were many similar examples without this degree of clarity...Note that the heater hose attaches directly to the pump casting nipple—without the use of a fitting. You're on the home stretch:
  7. pwbulldog (Simon)...The Mopar P/N 32002591 has been discontinued. I dug even further into aftermarket water pumps. Crown Automotive is a good barometer. All of the cast iron aftermarket water pumps for mid-seventies to 1990 AMC/Jeep 4.2L engines have a nipple cast into the water pump housing for the return heater hose. They do not use a fitting. In your latest close-up view of the water pump nipple (cast into the pump), it looks like the hose does fit directly onto the pump. Will the 5/8" hose fit over the casting nipple? If the hose fits properly, follow my original suggestions. Ignore the pipe thread, it's an option for those who need to block off this port. Yes, 1/4-inch NPT already restricts flow. Anything smaller would not work. Your water pump obviously does not require a fitting. Below is a typical Crown aftermarket cast iron replacement pump for 1975 up 4.2L engines. The pump has a cast-in hose nipple like your pump. If there is a thread, it's strictly for an NPT pipe plug for use when there is a need to block off the port: In looking at heater hose connector fittings, there is no 1/4" NPT fitting for a 5/8" heater hose—for the reason you cite. There would be inadequate flow. This is confirmation that your pump accepts the return hose without a fitting. Moses
  8. Simon, you're building a nice Jeep CJ-7! Keep up the detailed work on that engine...Let us know how the hose fitting issue works out. Moses
  9. Yes, Simon, that should do it for the late seventies style water pump. The factory service manual for your era shows the heater hose attaching directly to the water pump's integral nipple or bib. Take measurements. Measure the stem/shank of the nipple to confirm the hose I.D. size. This should match with the heater return pipe O.D. at the firewall. The thread on the water pump nipple could serve as a block-off if the vehicle does not have a heater. If a pipe thread, it would be tapered, most likely a 1/4-inch NPT pipe thread size. In the early eighties, AMC/Jeep 4.2L parts catalogs show a water pump design that does require a threaded heater hose fitting. In my Mopar parts catalog for 1981, there is a water pump that takes a threaded nipple (part #36 in this illustration below). The fitting used with this later water pump is factory/Mopar number: P/N 32002591 NIPPLE If your engine had this later style water pump, you would need a threaded nipple (Mopar 32002591 or equivalent). That water pump casting thread is likely 3/8" NPT or larger. The thread size you have on your pump is smaller than this. Your pump does not use a separate fitting for the hose. Instead, the hose attaches directly to the pump casting nipple. Moses
  10. Simon...Your photos and explanation are helpful. From what I see, there's good news. The cast fitting is part of the water pump. There should be no threads inside this water pump "fitting" or nipple. The heater hose fits directly over this casting nipple. There is no fitting required. I verified in the FSM for your Jeep model that the heater hose fits directly over this nipple. If you measure the nipple stem casting (below the neck), you will discover that the outside diameter of the nipple is close to the inside diameter of the heater hose that goes from the heater pipe at the firewall to the water pump. This is the return hose from the heater. The hose inside diameter/size can be smaller on this return hose than the hose size from the thermostat housing to the heater. Pay attention to the hose nipple and heater pipe sizes. When I install these heater hoses, I swab a light coating of Gasgacinch on the I.D. of the hose end or around the nipple. (In the day, I used a film of Permatex High Tack or Super 300D, which works fine.) This adds to the sealing ability at this casting nipple or bib, which if iron is usually not smooth. Do not apply too much sealant. Excess will find its way to the radiator core/tubes. Please confirm your findings... Moses
  11. Kevin G...The compression numbers are "okay", as expected for the mileage. The good news is that the high-to-low is relatively uniform, within 10 PSI is less good. If you're not using oil, rattling or knocking, the engine is sound for now. Based upon the transmission symptoms you share, here are the FSM possibilities...You should have the FSM (at least an inexpensive eBay CD or download version), and this information is available in the FSM for your model Jeep TJ: No Low Gear (Moves in 2nd or 3rd Gear Only): 1) Governor valve sticking: Remove governor, clean, inspect and repair as required. 2) Valve body malfunction: Remove, clean and inspect. Look for sticking 1-2 shift valve, 2-3 shift valve, governor plug or broken springs. 3) Front servo piston cocked in bore: Inspect servo and repair as required. 4) Front band linkage malfunction: Inspect linkage and look for bind in linkage. No Kickdown or Normal Downshift: 1) Throttle linkage misadjusted: Adjust linkage. 2) Accelerator pedal travel restricted: Floor mat under pedal, accelerator cable worn or brackets bent. 3) Governor/valve body hydraulic pressure too high or too low due to sticking governor, valve body malfunction or incorrect hydraulic control pressure adjustments: Perform hydraulic pressure tests to determine cause and repair as required. Correct valve body pressure adjustments as required. 4) Valve body malfunction: Perform hydraulic pressure tests to determine cause and repair as required. Correct valve body pressure adjustments as required. 5) Valve body malfunction: Sticking 1-2, 2-3 shift valves, or governor plugs. What I would do is backtrack to what you initially encountered: a disconnected TV cable. Perform a TV cable adjustment and make sure that the TV cable is connected on the inside of the transmission. Check the function of the TV cable, making sure that the TV cable is actually moving the throttle valve at the valve body. If in doubt, replace the TV cable. If that isn't the fix, start where two symptoms/malfunctions overlap. The governor and the valve body overlap, but don't start with the extra work of removing the valve body for cleaning and inspection. Start here: You want to know the relationship between a functional transmission, a loose TV cable and the subsequent malfunctioning shifts. If and when necessary, the governor and valve body can each be tested by running hydraulic pressure checks according to the FSM procedure. I made you a PDF copy of the FSM coverage. You can zoom into the document for easier reading. The converter stall test and clutch air apply tests are included: 30RH-32RH Pressure Checks PDF.pdf Pressure testing is a good diagnostic tool. You will need an automatic transmission pressure gauge to follow through with these tests. Moses
  12. Good question, Tawanda...In the late eighties, I covered Jack Clifford's shop at Southern California for OFF-ROAD Magazine. Jack and I had many discussions about inline six-cylinder engines. We each appreciated their virtues. Jack was among the earliest proponents of EFI conversions on inline sixes. The first systems Jack used were based on Ford's CPI, introduced on early eighties V-8 engines. CPI was Ford's response to GM TBI. An aftermarket company was making TBI conversions for Class A V-8 motorhome engines, replacing the large four-barrel carburetors. Jack adopted this system to a Jeep 258/4.2L inline six. This predates Mopar's first HESCO/Electromotive EFI conversion for the Jeep 258, which used an OEM Holley TBI unit from the Mopar V-8s. Straight eights like Buick's OHV 1941-42 engines optioned two carburetors. Hudson offered dual carburetors on the straight L-head six 308 Hornet postwar/fifties engines. Jack successfully raced Hudson drag cars with this engine. He became the go-to expert on inline sixes, including Chevrolet Stovebolts and the GMC Jimmys. There were a variety of multiple carburetor manifolds available for inline six hot rods during the postwar forties, fifties and sixties. Jack, however, concentrated on the challenge of even fuel mixtures to the outer cylinders of an inline six-cylinder engine with a centrally mounted, single two- or four-barrel carburetor. Jack Clifford designed his "ram" intake manifolds to produce better, more uniform air/fuel flow to the outer cylinders (#1 and #6). His Jeep 258/4.2L manifold took this approach. This manifold, originally designed for carburetion, is also well suited for an EFI/TBI conversion. If you were running Mopar MPI/EFI, each cylinder would have its own fuel injector with the fuel flow uniform and based upon the PCM signals. The intake manifold would essentially be a plenum for the throttle body to flow air (only) to each cylinder. You will not have that advantage with Howell or other TBI fuel injection systems. They will have the same challenges as a carburetor mounted centrally on an intake manifold: The Air/Fuel mixture merges at the TBI unit and flows through the intake manifold to each cylinder. Flow velocity and volume are based upon each cylinder's draw (vacuum or negative pressure) and the intake runner lengths. The outer cylinders have longer runs. So, yes, there is an advantage to using a Clifford manifold. The stock BBD Carter manifold is not bad, it's just not as efficient as the Clifford "ram" design. At low engine speeds and flow velocity, the issue would not be as extreme. Mid-range and higher rpm would benefit from a Clifford manifold. Torque would likely be improved incrementally over the entire rpm range from idle to redline...Your O2 sensor will be on the exhaust system (post combustion), so improved, more uniform flow and A/F ratio match per cylinder would gain incrementally from idle to redline. If you need to smog the Jeep, the Howell TBI system has 50-State legal E.O. status. Clifford manifolds do not have an E.O. number. Clifford does list a carburetor manifold for the 1991-up EFI cylinder head that would work with your head and Howell TBI. You will need an adapter to mate the GM/Howell TBI unit to a Howell/GM TBI unit. This is an additional aftermarket sourced part. A Clifford manifold could be an issue on the visual checklist for a California smog inspection. That would be nit-picky, though, as the key issue is the EFI/TBI. From what I understand, Howell TBI is usually an easy smog inspection. A California E.O. decal (50-State legal) comes with the package. These conversions always meet the tailpipe emissions threshold for a 258 in good condition. While on the subject of manifolds, you will need to run the 4.0L "header" type exhaust manifold with your cylinder head. (Clifford Performance makes an exhaust header—also without an E.O. number.) A '91-up OEM Mopar or equivalent aftermarket replacement manifold would work. This would meet your camshaft's requirements. Moses
  13. jordan89oak...You've really stepped up the game on your CJ-7. Looking back, you transformed this Jeep into a trail worthy, heavy duty vehicle. I like your attention to detail: The wire tying of the free-wheeling hub bolts, notorious for loosening on this five-bolt style hub, is very smart. The steering linkage and steering gear should be bulletproof. When you do the final front wheel alignment, make sure the steering gear is on its over-center position with the wheels pointed straight ahead. If this is a variable ratio steering gear, all the more important. You'll really value the twin-stick conversion on the Dana 300. This is a solid transfer case to start with, helical gears are a big plus, a good low range ratio. The twin-stick modes make the Dana 300 even more versatile. Good call... I'm impressed! You'll be thrilled when you can take advantage of all this work and the upgrades investment. Thanks for sharing your experience with us. The photos have been valuable, too! Moses
  14. Milder duration with stronger lift is a recipe for high manifold vacuum at an idle and low throttle openings plus better bottom end torque. I shared earlier that the main mission for trail crawling is to have the highest vacuum at idle, tip-in and low throttle positions. A longer duration camshaft will produce more horsepower at mid- and high rpm range while sacrificing idle and crawl speed manifold vacuum, torque and stability. LSA is lobe separation angle or, simply put for our purposes, valve overlap. Here is a quick reference to LSA: https://help.summitracing.com/app/answers/detail/a_id/4702/~/camshaft-lobe-separation Again, we're "stuck" with fixed valve timing, duration and valve lift on these AMC/Jeep inline six engines. The Schneider 1,000-3,500 rpm camshaft would likely be great on the Rubicon Trail. Control over tire-spin, idle without stalling, immediate throttle response as you tip-in the throttle. This camshaft is not for mud bog racing where you want higher horsepower in the mid-range and at high rpm. The shorter duration camshafts with lift improvement make stronger bottom end torque. Their horsepower peak and redline rpm will not seem impressive. When horsepower is the only objective, even with a diesel engine, high horsepower will come at a higher rpm ceiling. I happen to be a CompCams user and have known the company's R&D strategies since the eighties. I would likely try CompCams 197/201 rock crawl camshaft. Schneider's 256H camshaft would be an option.
  15. I like the Schneider profile for milder duration, good lift and the narrower lobe centers. That would work with either carburetion or aftermarket EFI as you have planned...What does Schneider share about that camshaft's intended use? Each of the camshafts we have reviewed offer good street/highway performance. Despite its rugged design, your 4.6L will seldom if ever see 4,000-4,500 rpm, especially if you gear it properly for the tire size. (Sand will be the highest rpm use.) Geared properly, your fuel efficiency should also be good.
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